text:
CDA

CDA, Cda, or CdA may refer to:

In education

 * Central Delta Academy, a private school in Mississippi
 * Certified dental assistant, in the United States
 * Child Development Associate, a credential in the early care and education
 * Communicative Disorders Assistant, a credential in assisting a registered Audiologist or Speech Language Pathologist, in Canada
 * Coram Deo Academy, a private Christian school in Flower Mound, Texas

Government agencies

 * Capital Development Authority, a kind of government entity
 * Capital Development Authority (Islamabad), the Capital Development Authority of Pakistan
 * Combined Development Agency, a uranium purchasing authority run by the US and UK government from 1948
 * Canadian Defence Academy, an organization in the Canadian Forces

Laws

 * Communications Decency Act, a US law found partially unconstitutional
 * Crime and Disorder Act 1998, a UK law

Other uses in law and government

 * Chargé d'Affaires
 * Confidential disclosure agreement
 * Criminal defense attorney

Political parties and lobbying groups

 * Christian Democratic Alliance (South Africa)
 * Christian Democrats of America, a Christian democratic organization in the US
 * Christian Democratic Appeal, a Christian democratic party in the Netherlands
 * College Democrats of America, the official youth outreach arm of the US Democratic Party
 * Conservative Democratic Alliance, in the UK

Other organizations

 * Catholic Daughters of the Americas, a Catholic women's charitable organization
 * Canadian Dental Association, an association of dentists in Canada
 * Diabetes Canada, which was known until 2017 as the Canadian Diabetes Association
 * Club de Deportes Antofagasta, a Chilean football club
 * Chinese Daoist Association

In chemistry

 * Chiral derivatizing agent, a type of chemical designed to react with enantiomers to indicate the enantiopurity
 * Completely denatured alcohol, the most heavily denatured alcohol

In computing

 * ".cda", a filename extension for a Compact Disc Audio track
 * Cellular digital accessory, a means to identify the software version of a mobile phone
 * Red Book (audio CD standard), Compact Disc Audio, the standard format for a CD
 * Content Delivery Application, a component of a typical content management system

In health and medicine

 * Canadian Dental Association, an association of dentists in Canada
 * Diabetes Canada, which was known until 2017 as the Canadian Diabetes Association
 * Chlorproguanil/dapsone/artesunate, an antimalarial drug
 * Clinical Document Architecture, a healthcare documentation standard
 * Congenital dyserythropoietic anemia, a blood condition
 * Cytidine deaminase, an enzyme
 * Communicative disorders assistant, a profession

In spaceflight

 * Command and data acquisition station, in spacecraft operations
 * Cosmic dust analyzer, an instrument on the Cassini–Huygens spacecraft

In mathematics

 * Cantor's diagonal argument, a proof technique in set theory

Other uses on science and technology

 * Canonical discriminant analysis, a type of linear discriminant analysis
 * Cda, abbreviation for the orchid genus Cochlioda, a synonym of Oncidium
 * Continuous descent approach, an aircraft approach method designed to reduce fuel burn and noise
 * Controlled droplet application, a concept for improving the efficiency of pesticide application
 * or drag area, the product of the drag coefficient and a reference area
 * , the drag area in automobile aerodynamics
 * Current differencing amplifier, amplifier taking current difference as input and voltage as output

Other uses

 * Caran d'Ache (company), a Swiss fine arts products company
 * Cardinia Road railway station, Melbourne
 * Coeur d'Alene (disambiguation), multiple meanings
 * Compañia Dominicana de Aviación, an airline from the Dominican Republic
 * Critical discourse analysis, in critical theory
 * Chantiers de l'Atlantique, French shipyard
 * Compressed Dry Air, term used in manufacturing and industry

zea:CDA

title: CDA


text:
Turquoise

Turquoise is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminium, with the chemical formula CuAl6(PO4)4(OH)8*4H2O. It is rare and valuable in finer grades and has been prized as a gemstone for millennia due to its hue.

Like most other opaque gems, turquoise has been devalued by the introduction of treatments, imitations, and synthetics into the market. The robin egg blue or sky blue color of the Persian turquoise mined near the modern city of Nishapur, Iran, has been used as a guiding reference for evaluating turquoise quality.

Names
The word turquoise dates to the 17th century and is derived from the Old French turquois meaning "Turkish" because the mineral was first brought to Europe through the Ottoman Empire. However, according to Etymonline, the word dates to the 14th century with the form turkeis, meaning "Turkish", which was replaced with turqueise from French in the 1560s. According to the same source, the gemstone was first brought to Europe from Turkestan or another Turkic territory. Pliny the Elder referred to the mineral as callais (from Ancient Greek κάλαϊς) and the Aztecs knew it as chalchihuitl.

Properties
The finest of turquoise reaches a maximum Mohs hardness of just under 6, or slightly more than window glass. Characteristically a cryptocrystalline mineral, turquoise almost never forms single crystals, and all of its properties are highly variable. X-ray diffraction testing shows its crystal system to be triclinic. With lower hardness comes greater porosity. The lustre of turquoise is typically waxy to subvitreous, and its transparency is usually opaque, but may be semitranslucent in thin sections. Colour is as variable as the mineral's other properties, ranging from white to a powder blue to a sky blue and from a blue-green to a yellowish green. The blue is attributed to idiochromatic copper while the green may be the result of iron impurities (replacing copper.)

The refractive index of turquoise varies from 1.61 to 1.65 on the three crystal axes, with birefringence 0.040, biaxial positive, as measured from rare single crystals.

Crushed turquoise is soluble in hot hydrochloric acid. Its streak is white to greenish to blue, and its fracture is smooth to conchoidal. Despite its low hardness relative to other gems, turquoise takes a good polish. Turquoise may also be peppered with flecks of pyrite or interspersed with dark, spidery limonite veining.

Turquoise is nearly always cryptocrystalline and massive and assumes no definite external shape. Crystals, even at the microscopic scale, are rare. Typically the form is a vein or fracture filling, nodular, or botryoidal in habit. Stalactite forms have been reported. Turquoise may also pseudomorphously replace feldspar, apatite, other minerals, or even fossils. Odontolite is fossil bone or ivory that has historically been thought to have been altered by turquoise or similar phosphate minerals such as the iron phosphate vivianite. Intergrowth with other secondary copper minerals such as chrysocolla is also common. Turquoise is distinguished from chrysocolla, the only common mineral with similar properties, by its greater hardness.

Turquoise forms a complete solid solution series with chalcosiderite, CuFe6(PO4)4(OH)8*4H2O, in which ferric iron replaces aluminium.

Formation
Turquoise deposits probably form in more than one way. However, a typical turquoise deposit begins with hydrothermal deposition of copper sulfides. This takes place when hydrothermal fluids leach copper from a host rock, which is typically an intrusion of calc-alkaline rock with a moderate to high silica content that is relatively oxidized. The copper is redeposited in more concentrated form as a copper porphyry, in which veins of copper sulfide fill joints and fractures in the rock. Deposition takes place mostly in the potassic alteration zone, which is characterized by conversion of existing feldspar to potassium feldspar and deposition of quartz and micas at a temperature of 400-600 C

Turquoise is a secondary or supergene mineral, not present in the original copper porphyry. It forms when meteoric water (rain or snow melt infiltrating the Earth's surface) percolates through the copper porphyry. Dissolved oxygen in the water oxidizes the copper sulfides to soluble sulfates, and the acidic, copper-laden solution then reacts with aluminum and potassium minerals in the host rock to precipitate turquoise. This typically fills veins in volcanic rock or phosphate-rich sediments. Deposition usually takes place at a relatively low temperature, 90-195 C, and seems to occur more readily in arid environments.

Turquoise in the Sinai Peninsula is found in lower Carboniferous sandstones overlain by basalt flows and upper Carboniferous limestone. The overlying beds were presumably the source of the copper, which precipitated as turquoise in nodules, horizontal seams, or vertical joints in the sandstone beds. The classical Iranian deposits are found in sandstones and limestones of Tertiary age were intruded by apatite-rich porphyritic trachytes and mafic rock. Supergene alteration fractured the rock and converted some of the minerals in the rock to alunite, which freed aluminum and phosphate to combine with copper from oxidized copper sulfides to form turquoise. This process took place at a relatively shallow depth, and by 1965 the mines had "bottomed" at a depth averaging just 9 m below the surface.

Turquoise deposits are widespread in North America. Some deposits, such as those of Saguache and Conejos Counties in Colorado or the Cerrillos Hills in New Mexico, are typical supergene deposits formed from copper porphyries. The deposits in Cochise County, Arizona, are found in Cambrian quartzites and geologically young granites and go down at least as deep as 54 m.

Occurrence
Turquoise was among the first gems to be mined, and many historic sites have been depleted, though some are still worked to this day. These are all small-scale operations, often seasonal owing to the limited scope and remoteness of the deposits. Most are worked by hand with little or no mechanization. However, turquoise is often recovered as a byproduct of large-scale copper mining operations, especially in the United States. Deposits typically take the form of small veins in partially decomposed volcanic rock in arid climates.

Iran
Iran has been an important source of turquoise for at least 2,000 years. It was initially named by Iranians "pērōzah" meaning "victory", and later the Arabs called it "fayrūzah", which is pronounced in Modern Persian as "fīrūzeh". In Iranian architecture, the blue turquoise was used to cover the domes of palaces because its intense blue colour was also a symbol of heaven on earth.

This deposit is blue naturally and turns green when heated due to dehydration. It is restricted to a mine-riddled region in Nishapur, the 2012 m mountain peak of Ali-mersai near Mashhad, the capital of Khorasan Province, Iran. Weathered and broken trachyte is host to the turquoise, which is found both in situ between layers of limonite and sandstone and amongst the scree at the mountain's base. These workings are the oldest known, together with those of the Sinai Peninsula. Iran also has turquoise mines in Semnan and Kerman provinces.

Sinai
Since at least the First Dynasty (3000 BCE) in ancient Egypt, and possibly before then, turquoise was used by the Egyptians and was mined by them in the Sinai Peninsula. This region was known as the Country of Turquoise by the native Monitu. There are six mines in the peninsula, all on its southwest coast, covering an area of some 650 km2. The two most important of these mines, from a historical perspective, are Serabit el-Khadim and Wadi Maghareh, believed to be among the oldest of known mines. The former mine is situated about 4 kilometres from an ancient temple dedicated to the deity Hathor.

The turquoise is found in sandstone that is, or was originally, overlain by basalt. Copper and iron workings are present in the area. Large-scale turquoise mining is not profitable today, but the deposits are sporadically quarried by Bedouin peoples using homemade gunpowder. In the rainy winter months, miners face a risk from flash flooding; even in the dry season, death from the collapse of the haphazardly exploited sandstone mine walls may occur. The colour of Sinai material is typically greener than that of Iranian material but is thought to be stable and fairly durable. Often referred to as "Egyptian turquoise", Sinai material is typically the most translucent, and under magnification, its surface structure is revealed to be peppered with dark blue discs not seen in material from other localities.

United States

The Southwest United States is a significant source of turquoise; Arizona, California (San Bernardino, Imperial, Inyo counties), Colorado (Conejos, El Paso, Lake, Saguache counties), New Mexico (Eddy, Grant, Otero, Santa Fe counties) and Nevada (Clark, Elko, Esmeralda County, Eureka, Lander, Mineral County and Nye counties) are (or were) especially rich. The deposits of California and New Mexico were mined by pre-Columbian Native Americans using stone tools, some local and some from as far away as central Mexico. Cerrillos, New Mexico is thought to be the location of the oldest mines; prior to the 1920s, the state was the country's largest producer; it is more or less exhausted today. Only one mine in California, located at Apache Canyon, operates at a commercial capacity today.

The turquoise occurs as vein or seam fillings, and as compact nuggets; these are mostly small in size. While quite fine material is sometimes found, rivalling Iranian material in both colour and durability, most American turquoise is of a low grade (called "chalk turquoise"); high iron levels mean greens and yellows predominate, and a typically friable consistency in the turquoise's untreated state precludes use in jewelry.

Arizona is currently the most important producer of turquoise by value. Several mines exist in the state, two of them famous for their unique colour and quality and considered the best in the industry: the Sleeping Beauty Mine in Globe ceased turquoise mining in August 2012. The mine chose to send all ore to the crusher and to concentrate on copper production due to the rising price of copper on the world market. The price of natural untreated Sleeping Beauty turquoise has risen dramatically since the mine's closing. The Kingman Mine as of 2015 still operates alongside a copper mine outside of the city. Other mines include the Blue Bird mine, Castle Dome, and Ithaca Peak, but they are mostly inactive due to the high cost of operations and federal regulations. The Phelps Dodge Lavender Pit mine at Bisbee ceased operations in 1974 and never had a turquoise contractor. All Bisbee turquoise was "lunch pail" mined. It came out of the copper ore mine in miners' lunch pails. Morenci and Turquoise Peak are either inactive or depleted.

Nevada is the country's other major producer, with more than 120 mines which have yielded significant quantities of turquoise. Unlike elsewhere in the US, most Nevada mines have been worked primarily for their gem turquoise and very little has been recovered as a byproduct of other mining operations. Nevada turquoise is found as nuggets, fracture fillings and in breccias as the cement filling interstices between fragments. Because of the geology of the Nevada deposits, a majority of the material produced is hard and dense, being of sufficient quality that no treatment or enhancement is required. While nearly every county in the state has yielded some turquoise, the chief producers are in Lander and Esmeralda counties. Most of the turquoise deposits in Nevada occur along a wide belt of tectonic activity that coincides with the state's zone of thrust faulting. It strikes at a bearing of about 15° and extends from the northern part of Elko County, southward down to the California border southwest of Tonopah. Nevada has produced a wide diversity of colours and mixes of different matrix patterns, with turquoise from Nevada coming in various shades of blue, blue-green, and green. Some of this unusually-coloured turquoise may contain significant zinc and iron, which is the cause of the beautiful bright green to yellow-green shades. Some of the green to green-yellow shades may actually be variscite or faustite, which are secondary phosphate minerals similar in appearance to turquoise. A significant portion of the Nevada material is also noted for its often attractive brown or black limonite veining, producing what is called "spiderweb matrix". While a number of the Nevada deposits were first worked by Native Americans, the total Nevada turquoise production since the 1870s has been estimated at more than 600 ST, including nearly 400 ST from the Carico Lake mine. In spite of increased costs, small scale mining operations continue at a number of turquoise properties in Nevada, including the Godber, Orvil Jack and Carico Lake mines in Lander County, the Pilot Mountain Mine in Mineral County, and several properties in the Royston and Candelaria areas of Esmerelda County.

In 1912, the first deposit of distinct, single-crystal turquoise was discovered at Lynch Station in Campbell County, Virginia. The crystals, forming a druse over the mother rock, are very small; 1 mm is considered large. Until the 1980s Virginia was widely thought to be the only source of distinct crystals; there are now at least 27 other localities.

In an attempt to recoup profits and meet demand, some American turquoise is treated or enhanced to a certain degree. These treatments include innocuous waxing and more controversial procedures, such as dyeing and impregnation (see Treatments). There are some American mines which produce materials of high enough quality that no treatment or alterations are required. Any such treatments which have been performed should be disclosed to the buyer on sale of the material.

Other sources
Turquoise prehistoric artifacts (beads) are known since the fifth millennium BCE from sites in the Eastern Rhodopes in Bulgaria – the source for the raw material is possibly related to the nearby Spahievo lead–zinc ore field.

China has been a minor source of turquoise for 3,000 years or more. Gem-quality material, in the form of compact nodules, is found in the fractured, silicified limestone of Yunxian and Zhushan, Hubei province. Additionally, Marco Polo reported turquoise found in present-day Sichuan. Most Chinese material is exported, but a few carvings worked in a manner similar to jade exist. In Tibet, gem-quality deposits purportedly exist in the mountains of Derge and Nagari-Khorsum in the east and west of the region respectively.

Other notable localities include: Afghanistan; Australia (Victoria and Queensland); north India; northern Chile (Chuquicamata); Cornwall; Saxony; Silesia; and Turkestan.

History of use

The pastel shades of turquoise have endeared it to many great cultures of antiquity: it has adorned the rulers of Ancient Egypt, the Aztecs (and possibly other Pre-Columbian Mesoamericans), Persia, Mesopotamia, the Indus Valley, and to some extent in ancient China since at least the Shang dynasty. Despite being one of the oldest gems, probably first introduced to Europe (through Turkey) with other Silk Road novelties, turquoise did not become important as an ornamental stone in the West until the 14th century, following a decline in the Roman Catholic Church's influence which allowed the use of turquoise in secular jewellery. It was apparently unknown in India until the Mughal period, and unknown in Japan until the 18th century. A common belief shared by many of these civilizations held that turquoise possessed certain prophylactic qualities; it was thought to change colour with the wearer's health and protect him or her from untoward forces.

The Aztecs viewed turquoise as an embodiment of fire and gave it properties such as heat and smokiness. They inlaid turquoise, together with gold, quartz, malachite, jet, jade, coral, and shells, into provocative (and presumably ceremonial) mosaic objects such as masks (some with a human skull as their base), knives, and shields. Natural resins, bitumen and wax were used to bond the turquoise to the objects' base material; this was usually wood, but bone and shell were also used. Like the Aztecs, the Pueblo, Navajo and Apache tribes cherished turquoise for its amuletic use; the latter tribe believe the stone to afford the archer dead aim. In Navajo culture it is used for "a spiritual protection and blessing." Among these peoples turquoise was used in mosaic inlay, in sculptural works, and was fashioned into toroidal beads and freeform pendants. The Ancestral Puebloans (Anasazi) of the Chaco Canyon and surrounding region are believed to have prospered greatly from their production and trading of turquoise objects. The distinctive silver jewellery produced by the Navajo and other Southwestern Native American tribes today is a rather modern development, thought to date from around 1880 as a result of European influences.

In Persia, turquoise was the de facto national stone for millennia, extensively used to decorate objects (from turbans to bridles), mosques, and other important buildings both inside and out, such as the Medresseh-i Shah Husein Mosque of Isfahan. The Persian style and use of turquoise was later brought to India following the establishment of the Mughal Empire there, its influence seen in high purity gold jewellery (together with ruby and diamond) and in such buildings as the Taj Mahal. Persian turquoise was often engraved with devotional words in Arabic script which was then inlaid with gold.

Cabochons of imported turquoise, along with coral, was (and still is) used extensively in the silver and gold jewellery of Tibet and Mongolia, where a greener hue is said to be preferred. Most of the pieces made today, with turquoise usually roughly polished into irregular cabochons set simply in silver, are meant for inexpensive export to Western markets and are probably not accurate representations of the original style.

The Ancient Egyptian use of turquoise stretches back as far as the First Dynasty and possibly earlier; however, probably the most well-known pieces incorporating the gem are those recovered from Tutankhamun's tomb, most notably the Pharaoh's iconic burial mask which was liberally inlaid with the stone. It also adorned rings and great sweeping necklaces called pectorals. Set in gold, the gem was fashioned into beads, used as inlay, and often carved in a scarab motif, accompanied by carnelian, lapis lazuli, and in later pieces, coloured glass. Turquoise, associated with the goddess Hathor, was so liked by the Ancient Egyptians that it became (arguably) the first gemstone to be imitated, the fair structure created by an artificial glazed ceramic product known as faience.

The French conducted archaeological excavations of Egypt from the mid-19th century through the early 20th. These excavations, including that of Tutankhamun's tomb, created great public interest in the western world, subsequently influencing jewellery, architecture, and art of the time. Turquoise, already favoured for its pastel shades since around 1810, was a staple of Egyptian Revival pieces. In contemporary Western use, turquoise is most often encountered cut en cabochon in silver rings, bracelets, often in the Native American style, or as tumbled or roughly hewn beads in chunky necklaces. Lesser material may be carved into fetishes, such as those crafted by the Zuni. While strong sky blues remain superior in value, mottled green and yellowish material is popular with artisans.

Cultural associations
In many cultures of the Old and New Worlds, this gemstone has been esteemed for thousands of years as a holy stone, a bringer of good fortune or a talisman. The oldest evidence for this claim was found in Ancient Egypt, where grave furnishings with turquoise inlay were discovered, dating from approximately 3000 BCE. In the ancient Persian Empire, the sky-blue gemstones were earlier worn round the neck or wrist as protection against unnatural death. If they changed colour, the wearer was thought to have reason to fear the approach of doom. Meanwhile, it has been discovered that the turquoise certainly can change colour, but that this is not necessarily a sign of impending danger. The change can be caused by the light, or by a chemical reaction brought about by cosmetics, dust or the acidity of the skin.

The goddess Hathor was associated with turquoise, as she was the patroness of Serabit el-Khadim, where it was mined. Her titles included "Lady of Turquoise", "Mistress of Turquoise", and "Lady of Turquoise Country".

In Western culture, turquoise is also the traditional birthstone for those born in the month of December. The turquoise is also a stone in the Jewish High Priest's breastplate, described in Exodus chapter 28. The stone is also considered sacred to the indigenous Zuni and Pueblo peoples of the American Southwest. The pre-Columbian Aztec and Maya also considered it to be a valuable and culturally important stone.

Imitations

The Egyptians were the first to produce an artificial imitation of turquoise, in the glazed earthenware product faience. Later glass and enamel were also used, and in modern times more sophisticated porcelain, plastics, and various assembled, pressed, bonded, and sintered products (composed of various copper and aluminium compounds) have been developed: examples of the latter include "Viennese turquoise", made from precipitated aluminium phosphate coloured by copper oleate; and "neolith", a mixture of bayerite and copper(II) phosphate. Most of these products differ markedly from natural turquoise in both physical and chemical properties, but in 1972 Pierre Gilson introduced one fairly close to a true synthetic (it does differ in chemical composition owing to a binder used, meaning it is best described as a simulant rather than a synthetic). Gilson turquoise is made in both a uniform colour and with black "spiderweb matrix" veining not unlike the natural Nevada material.

The most common imitation of turquoise encountered today is dyed howlite and magnesite, both white in their natural states, and the former also having natural (and convincing) black veining similar to that of turquoise. Dyed chalcedony, jasper, and marble is less common, and much less convincing. Other natural materials occasionally confused with or used in lieu of turquoise include: variscite and faustite; chrysocolla (especially when impregnating quartz); lazulite; smithsonite; hemimorphite; wardite; and a fossil bone or tooth called odontolite or "bone turquoise", coloured blue naturally by the mineral vivianite. While rarely encountered today, odontolite was once mined in large quantities—specifically for its use as a substitute for turquoise—in southern France.

These fakes are detected by gemologists using a number of tests, relying primarily on non-destructive, close examination of surface structure under magnification; a featureless, pale blue background peppered by flecks or spots of whitish material is the typical surface appearance of natural turquoise, while manufactured imitations will appear radically different in both colour (usually a uniform dark blue) and texture (usually granular or sugary). Glass and plastic will have a much greater translucency, with bubbles or flow lines often visible just below the surface. Staining between grain boundaries may be visible in dyed imitations.

Some destructive tests may be necessary; for example, the application of diluted hydrochloric acid will cause the carbonates odontolite and magnesite to effervesce and howlite to turn green, while a heated probe may give rise to the pungent smell so indicative of plastic. Differences in specific gravity, refractive index, light absorption (as evident in a material's absorption spectrum), and other physical and optical properties are also considered as means of separation.

Treatments
Turquoise is treated to enhance both its colour and durability (increased hardness and decreased porosity). As is so often the case with any precious stones, full disclosure about treatment is frequently not given. Gemologists can detect these treatments using a variety of testing methods, some of which are destructive, such as the use of a heated probe applied to an inconspicuous spot, which will reveal oil, wax or plastic treatment.

Waxing and oiling
Historically, light waxing and oiling were the first treatments used in ancient times, providing a wetting effect, thereby enhancing the colour and lustre. This treatment is more or less acceptable by tradition, especially because treated turquoise is usually of a higher grade to begin with. Oiled and waxed stones are prone to "sweating" under even gentle heat or if exposed to too much sun, and they may develop a white surface film or bloom over time. (With some skill, oil and wax treatments can be restored.)

Backing
Since finer turquoise is often found as thin seams, it may be glued to a base of stronger foreign material for reinforcement. These stones are termed "backed", and it is standard practice that all thinly cut turquoise in the Southwestern United States is backed. Native indigenous peoples of this region, because of their considerable use and wearing of turquoise, have found that backing increases the durability of thinly cut slabs and cabochons of turquoise. They observe that if the stone is not backed it will often crack. Backing of turquoise is not widely known outside of the Native American and Southwestern United States jewellery trade. Backing does not diminish the value of high quality turquoise, and indeed the process is expected for most thinly cut American commercial gemstones.

Zachery treatment
A proprietary process was created by electrical engineer and turquoise dealer James E. Zachery in the 1980s to improve the stability of medium to high-grade turquoise. The process can be applied in several ways: either through deep penetration on rough turquoise to decrease porosity, by shallow treatment of finished turquoise to enhance color, or both. The treatment can enhance color and improve the turquoise's ability to take a polish. Such treated turquoise can be distinguished in some cases from natural turquoise, without destruction, by energy-dispersive X-ray spectroscopy, which can detect its elevated potassium levels. In some instances, such as with already high-quality, low-porosity turquoise that is treated only for porosity, the treatment is undetectable.

Dyeing
The use of Prussian blue and other dyes (often in conjunction with bonding treatments) to "enhance” its appearance, make uniform or completely change the colour, is regarded as fraudulent by some purists, especially since some dyes may fade or rub off on the wearer. Dyes have also been used to darken the veins of turquoise.

Stabilization
Material treated with plastic or water glass is termed "bonded" or "stabilized" turquoise. This process consists of pressure impregnation of otherwise unsaleable chalky American material by epoxy and plastics (such as polystyrene) and water glass (sodium silicate) to produce a wetting effect and improve durability. Plastic and water glass treatments are far more permanent and stable than waxing and oiling, and can be applied to material too chemically or physically unstable for oil or wax to provide sufficient improvement. Conversely, stabilization and bonding are rejected by some as too radical an alteration.

The epoxy binding technique was first developed in the 1950s and has been attributed to Colbaugh Processing of Arizona, a company that still operates today.

Reconstitution
Perhaps the most extreme of treatments is "reconstitution", wherein fragments of fine turquoise material, too small to be used individually, are powdered and then bonded with resin to form a solid mass. Very often the material sold as "reconstituted turquoise" is artificial, with little or no natural stone, made entirely from resins and dyes. In the trade reconstituted turquoise is often called "block turquoise" or simply "block".

Valuation and care
Hardness and richness of colour are two of the major factors in determining the value of turquoise; while colour is a matter of individual taste, generally speaking, the most desirable is a strong sky to robin egg blue (in reference to the eggs of the American robin). Whatever the colour, for many applications, turquoise should not be soft or chalky; even if treated, such lesser material (to which most turquoise belongs) is liable to fade or discolour over time and will not hold up to normal use in jewellery.

The mother rock or matrix in which turquoise is found can often be seen as splotches or a network of brown or black veins running through the stone in a netted pattern; this veining may add value to the stone if the result is complementary, but such a result is uncommon. Such material is sometimes described as "spiderweb matrix"; it is most valued in the Southwest United States and Far East, but is not highly appreciated in the Near East where unblemished and vein-free material is ideal (regardless of how complementary the veining may be). Uniformity of colour is desired, and in finished pieces the quality of workmanship is also a factor; this includes the quality of the polish and the symmetry of the stone. Calibrated stones—that is, stones adhering to standard jewellery setting measurements—may also be more sought after. Like coral and other opaque gems, turquoise is commonly sold at a price according to its physical size in millimetres rather than weight.

Turquoise is treated in many different ways, some more permanent and radical than others. Controversy exists as to whether some of these treatments should be acceptable, but one can be more or less forgiven universally: This is the light waxing or oiling applied to most gem turquoise to improve its colour and lustre; if the material is of high quality to begin with, very little of the wax or oil is absorbed and the turquoise therefore does not rely on this impermanent treatment for its beauty. All other factors being equal, untreated turquoise will always command a higher price. Bonded and reconstituted material is worth considerably less.

Being a phosphate mineral, turquoise is inherently fragile and sensitive to solvents; perfume and other cosmetics will attack the finish and may alter the colour of turquoise gems, as will skin oils, as will most commercial jewellery cleaning fluids. Prolonged exposure to direct sunlight may also discolour or dehydrate turquoise. Care should therefore be taken when wearing such jewels: cosmetics, including sunscreen and hair spray, should be applied before putting on turquoise jewellery, and they should not be worn to a beach or other sun-bathed environment. After use, turquoise should be gently cleaned with a soft cloth to avoid a buildup of residue, and should be stored in its own container to avoid scratching by harder gems. Turquoise can also be adversely affected if stored in an airtight container.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Turquoise


text:
Mirage

A mirage is a naturally-occurring optical phenomenon in which light rays bend via refraction to produce a displaced image of distant objects or the sky. The word comes to English via the French (se) mirer, from the Latin mirari, meaning "to look at, to wonder at".

Mirages can be categorized as "inferior" (meaning lower), "superior" (meaning higher) and "Fata Morgana", one kind of superior mirage consisting of a series of unusually elaborate, vertically stacked images, which form one rapidly-changing mirage.

In contrast to a hallucination, a mirage is a real optical phenomenon that can be captured on camera, since light rays are actually refracted to form the false image at the observer's location. What the image appears to represent, however, is determined by the interpretive faculties of the human mind. For example, inferior images on land are very easily mistaken for the reflections from a small body of water.

Inferior mirage
In an inferior mirage, the mirage image appears below the real object. The real object in an inferior mirage is the (blue) sky or any distant (therefore bluish) object in that same direction. The mirage causes the observer to see a bright and bluish patch on the ground.

Light rays coming from a particular distant object all travel through nearly the same layers of air, and all are refracted at about the same angle. Therefore, rays coming from the top of the object will arrive lower than those from the bottom. The image is usually upside-down, enhancing the illusion that the sky image seen in the distance is a specular reflection on a puddle of water or oil acting as a mirror.

While the aero-dynamics are highly active, the image of the inferior mirage is stable unlike the fata morgana which can change within seconds. Since warmer air rises while cooler air (being denser) sinks, the layers will mix, causing turbulence. The image will be distorted accordingly; it may vibrate or be stretched vertically (towering) or compressed vertically (stooping). A combination of vibration and extension are also possible. If several temperature layers are present, several mirages may mix, perhaps causing double images. In any case, mirages are usually not larger than about half a degree high (roughly the angular diameter of the Sun and Moon) and are from objects between dozens of meters and a few kilometers away.

Heat haze
Heat haze, also called heat shimmer, refers to the inferior mirage observed when viewing objects through a mass of heated air. Common instances when heat haze occurs include images of objects viewed across asphalt concrete (also known as tarmac), roads and over masonry rooftops on hot days, above and behind fire (as in burning candles, patio heaters, and campfires), and through exhaust gases from jet engines. When appearing on roads due to the hot asphalt, it is often referred to as a "highway mirage". It also occurs in deserts; in that case, it is referred to as a "desert mirage". Both tarmac and sand can become very hot when exposed to the sun, easily being more than 10 C-change higher than the air above, enough to make conditions suitable to cause the mirage.

Convection causes the temperature of the air to vary, and the variation between the hot air at the surface of the road and the denser cool air above it causes a gradient in the refractive index of the air. This produces a blurred shimmering effect, which hinders the ability to resolve the image and increases when the image is magnified through a telescope or telephoto lens.

Light from the sky at a shallow angle to the road is refracted by the index gradient, making it appear as if the sky is reflected by the road's surface. This might appear as a pool of liquid (usually water, but possibly others, such as oil) on the road, as some types of liquid also reflect the sky. The illusion moves into the distance as the observer approaches the miraged object giving one the same effect as approaching a rainbow.

Heat haze is not related to the atmospheric phenomenon of haze.

Superior mirage
A superior mirage is one in which the mirage image appears to be located above the real object. A superior mirage occurs when the air below the line of sight is colder than the air above it. This unusual arrangement is called a temperature inversion, since warm air above cold air is the opposite of the normal temperature gradient of the atmosphere during the daytime. Passing through the temperature inversion, the light rays are bent down, and so the image appears above the true object, hence the name superior.

Superior mirages are quite common in polar regions, especially over large sheets of ice that have a uniform low temperature. Superior mirages also occur at more moderate latitudes, although in those cases they are weaker and tend to be less smooth and stable. For example, a distant shoreline may appear to tower and look higher (and, thus, perhaps closer) than it really is. Because of the turbulence, there appear to be dancing spikes and towers. This type of mirage is also called the Fata Morgana, or hafgerðingar in the Icelandic language.

A superior mirage can be right-side up or upside-down, depending on the distance of the true object and the temperature gradient. Often the image appears as a distorted mixture of up and down parts.

Since the earth is round, if the downward bending curvature of light rays is about the same as the curvature of Earth, light rays can travel large distances, including from beyond the horizon. This was observed and documented in 1596, when a ship in search of the Northeast passage became stuck in the ice at Novaya Zemlya, above the Arctic Circle. The Sun appeared to rise two weeks earlier than expected; the real Sun had still been below the horizon, but its light rays followed the curvature of Earth. This effect is often called a Novaya Zemlya mirage. For every 111.12 km that light rays travel parallel to Earth's surface, the Sun will appear 1° higher on the horizon. The inversion layer must have just the right temperature gradient over the whole distance to make this possible.

In the same way, ships that are so far away that they should not be visible above the geometric horizon may appear on or even above the horizon as superior mirages. This may explain some stories about flying ships or coastal cities in the sky, as described by some polar explorers. These are examples of so-called Arctic mirages, or hillingar in Icelandic.

If the vertical temperature gradient is +12.9 C-change per 100 m (where the positive sign means the temperature increases at higher altitudes) then horizontal light rays will just follow the curvature of Earth, and the horizon will appear flat. If the gradient is less (as it almost always is) the rays are not bent enough and get lost in space, which is the normal situation of a spherical, convex "horizon".

In some situations, distant objects can be elevated or lowered, stretched or shortened with no mirage involved.

Fata Morgana
A Fata Morgana (the name comes from the Italian translation of Morgan le Fay, the fairy, shapeshifting half-sister of King Arthur) is a very complex superior mirage. It appears with alternations of compressed and stretched areas, erect images, and inverted images. A Fata Morgana is also a fast-changing mirage.

Fata Morgana mirages are most common in polar regions, especially over large sheets of ice with a uniform low temperature, but they can be observed almost anywhere. In polar regions, a Fata Morgana may be observed on cold days; in desert areas and over oceans and lakes, a Fata Morgana may be observed on hot days. For a Fata Morgana, temperature inversion has to be strong enough that light rays' curvatures within the inversion are stronger than the curvature of Earth.

The rays will bend and form arcs. An observer needs to be within an atmospheric duct to be able to see a Fata Morgana. Fata Morgana mirages may be observed from any altitude within Earth's atmosphere, including from mountaintops or airplanes.

Distortions of image and bending of light can produce spectacular effects. In his book Pursuit: The Chase and Sinking of the "Bismarck", Ludovic Kennedy describes an incident that allegedly took place below the Denmark Strait during 1941, following the sinking of the Hood. The Bismarck, while pursued by the British cruisers Norfolk and Suffolk, passed out of sight into a sea mist. Within a matter of seconds, the ship re-appeared steaming toward the British ships at high speed. In alarm the cruisers separated, anticipating an imminent attack, and observers from both ships watched in astonishment as the German battleship fluttered, grew indistinct and faded away. Radar watch during these events indicated that the Bismarck had in fact made no change to her course.

Night-time mirages
The conditions for producing a mirage can occur at night as well as during the day. Under some circumstances mirages of astronomical objects and mirages of lights from moving vehicles, aircraft, ships, buildings, etc. can be observed at night.

Mirage of astronomical objects
A mirage of an astronomical object is a naturally occurring optical phenomenon in which light rays are bent to produce distorted or multiple images of an astronomical object. Mirages can be observed for such astronomical objects as the Sun, the Moon, the planets, bright stars, and very bright comets. The most commonly observed are sunset and sunrise mirages.

title: Mirage


text:
Parenting

Parenting or child rearing promotes and supports the physical, emotional, social, spiritual and cognitive development of a child from infancy to adulthood. Parenting refers to the intricacies of raising a child and not exclusively for a biological relationship.

The most common caretakers in parenting are the biological parents of the child in question. However, a caretaker may be an older sibling, step-parent, grandparent, legal guardian, aunt, uncle, other family members, or a family friend. Governments and society may also have a role in child-rearing or upbringing. In many cases, orphaned or abandoned children receive parental care from non-parent or non-blood relations. Others may be adopted, raised in foster care, or placed in an orphanage. Parenting skills vary, and a parent or surrogate with good parenting skills may be referred to as a good parent.

Parenting styles vary by historical period, race/ethnicity, social class, preference, and a few other social features. Additionally, research supports that parental history, both in terms of attachments of varying quality and parental psychopathology, particularly in the wake of adverse experiences, can strongly influence parental sensitivity and child outcomes. Parenting may have long-term impacts on adoptive children as well, as recent research has shown that warm adoptive parenting reduces internalizing and externalizing problems of the adoptive children over time.

Factors that affect decisions
Social class, wealth, culture and income have a very strong impact on what methods of child rearing parents use. Cultural values play a major role in how a parent raises their child. However, parenting is always evolving, as times, cultural practices, social norms, and traditions change. Studies on these factors affecting parenting decisions have shown just that.

In psychology, the parental investment theory suggests that basic differences between males and females in parental investment have great adaptive significance and lead to gender differences in mating propensities and preferences.

Styles
A parenting style is indicative of the overall emotional climate in the home. Developmental psychologist Diana Baumrind proposed three main parenting styles in early child development: authoritative, authoritarian, and permissive. These parenting styles were later expanded to four to include an uninvolved style. These four styles involve combinations of acceptance and responsiveness, and also involve demand and control. Research has found that parenting style is significantly related to a child's subsequent mental health and well-being. In particular, authoritative parenting is positively related to mental health and satisfaction with life, and authoritarian parenting is negatively related to these variables. With authoritarian and permissive parenting on opposite sides of the spectrum, most conventional modern models of parenting fall somewhere in between. Although it is influential, Baumrind's typology has received significant criticism for containing overly broad categorizations and an imprecise and overly idealized description of authoritative parenting.

Authoritative parenting
Described by Baumrind as the "just right" style, it combines medium level demands on the child and a medium level responsiveness from the parents. Authoritative parents rely on positive reinforcement and infrequent use of punishment. Parents are more aware of a child's feelings and capabilities and support the development of a child's autonomy within reasonable limits. There is a give-and-take atmosphere involved in parent-child communication, and both control and support are balanced. Some research has shown that this style of parenting is more beneficial than the too-hard authoritarian style or the too-soft permissive style. These children score higher in terms of competence, mental health, and social development than those raised in permissive, authoritarian, or neglectful homes. However, Dr. Wendy Grolnick has critiqued Baumrind's use of the term "firm control" in her description of authoritative parenting and argued that there should be clear differentiation between coercive power assertion (which is associated with negative effects on children) and the more positive practices of structure and high expectations.

Authoritarian parenting
Authoritarian parents are very rigid and strict. High demands are placed on the child, but there is little responsiveness to them. Parents who practice authoritarian-style parenting have a non-negotiable set of rules and expectations strictly enforced and require rigid obedience. When the rules are not followed, punishment is often used to promote and ensure future compliance. There is usually no explanation of punishment except that the child is in trouble for breaking a rule. This parenting style is strongly associated with corporal punishment, such as spanking. A typical response to a child's question of authority would be, "because I said so." This type of parenting seems to be seen more often in working-class families than in the middle class. In 1983, Diana Baumrind found that children raised in an authoritarian-style home were less cheerful, moodier, and more vulnerable to stress. In many cases, these children also demonstrated passive hostility. This parenting style can negatively impact the educational success and career path, while a firm and reassuring parenting style impact positively.

Permissive parenting
Permissive parenting has become a more popular parenting method for middle-class families than working-class families roughly since the end of WWII. In these settings, a child's freedom and autonomy are highly valued, and parents rely primarily on reasoning and explanation. Parents are undemanding, and thus there tends to be little if any punishment or explicit rules in this parenting style. These parents say that their children are free from external constraints and tend to be highly responsive to whatever it is that the child wants. Children of permissive parents are generally happy but sometimes show low levels of self-control and self-reliance because they lack structure at home. Author Alfie Kohn criticized the study and categorization of permissive parenting, arguing that it serves to "blur the differences between 'permissive' parents who were really just confused and those who were deliberately democratic."

Uninvolved parenting
An uninvolved or neglectful parenting style is when parents are often emotionally or physically absent. They have little to no expectations from the child and regularly have no communication. They are not responsive to a child's needs and have little to no behavioral expectations. They may consider their children to be "emotionally priceless" and may not engage with them and believe they are giving the child its personal space. If present, they may provide what the child needs for survival with little to no engagement. There is often a large gap between parents and children with this parenting style. Children with little or no communication with their own parents tend to be victimized by other children and may exhibit deviant behavior themselves. Children of uninvolved parents suffer in social competence, academic performance, psychosocial development, and problematic behavior.

Intrusive parenting
Intrusive parenting is when parents use "parental control and inhibition of adolescents' thoughts, feelings, and emotional expression through the use of love withdrawal, guilt induction, and manipulative tactics" for protecting them from the possible pitfalls, without knowing it can deprive/disturb the adolescents' development and growth period. Intrusive parents may try to set unrealistic expectations on their children by overestimating their intellectual capability and underestimating their physical capability or developmental capability, like enrolling them into more extracurricular activities or enrolling them into certain classes without understanding their child's passion, and it may eventually lead children not taking ownership of activities or develop behavioral problems. Children, especially adolescents might become victims and be "unassertive, avoid confrontation, being eager to please others, and suffer from low self-esteem." They may compare their children to others, like friends and family, and also force their child to be codependent—to a point where the children feel unprepared when they go into the world. Research has shown that this parenting style can lead to "greater under-eating behaviors, risky cyber behaviors, substance use, and depressive symptoms among adolescents."

Unconditional parenting
Unconditional parenting refers to a parenting approach that is focused on the whole child, emphasizes working with a child to solve problems, and views parental love as a gift. It contrasts with conditional parenting, which focuses on the child's behavior, emphasizes controlling children using rewards and punishments, and views parental love as a privilege to be earned. The concept of unconditional parenting was popularized by author Alfie Kohn in his 2005 book Unconditional Parenting: Moving from Rewards and Punishments to Love and Reason. Kohn differentiates unconditional parenting from what he sees as the caricature of permissive parenting by arguing that parents can be anti-authoritarian and opposed to exerting control while also recognizing the value of respectful adult guidance and a child's need for non-coercive structure in their lives.

Trustful parenting
Trustful parenting is a child-centered parenting style in which parents trust their children to make decisions, play and explore on their own, and learn from their own mistakes. Research professor Peter Gray argues that trustful parenting was the dominant parenting style in prehistoric hunter-gatherer societies. Gray contrasts trustful parenting with "directive-domineering" parenting, which emphasizes controlling children to train them in obedience (historically involving using child labor to teach subservience to lords and masters), and "directive-protective" parenting, which involves controlling children to protect them from harm. Gray argues that the directive-domineering approach became the predominant parenting style with the spread of agriculture and industry, while the directive-protective approach took over as the dominant approach in the late 20th century.

Practices

A parenting practice is a specific behavior that a parent uses in raising a child. These practices are used to socialize children. Kuppens et al. found that "researchers have identified overarching parenting dimensions that reflect similar parenting practices, mostly by modeling the relationships among these parenting practices using factor analytic techniques." For example, many parents read aloud to their offspring in the hopes of supporting their linguistic and intellectual development. In cultures with strong oral traditions, such as Indigenous American communities and New Zealand Maori communities, storytelling is a critical parenting practice for children.

Parenting practices reflect the cultural understanding of children. Parents in individualistic countries like Germany spend more time engaged in face-to-face interaction with babies and more time talking to the baby about the baby. Parents in more communal cultures, such as West African cultures, spend more time talking to the baby about other people and more time with the baby facing outwards so that the baby sees what the mother sees.

Skills and behaviors
Parenting skills and behaviors assist parents in leading children into healthy adulthood and development of the child's social skills. The cognitive potential, social skills, and behavioral functioning a child acquires during the early years are positively correlated with the quality of their interactions with their parents.

According to the Canadian Council on Learning, children benefit (or avoid poor developmental outcomes) when their parents:
 * 1) Communicate truthfully about events: Authenticity from parents who explain can help their children understand what happened and how they are involved;
 * 2) Maintain consistency: Parents that regularly institute routines can see benefits in their children's behavioral patterns;
 * 3) Utilize resources available to them, reaching out into the community and building a supportive social network;
 * 4) Take an interest in their child's educational and early developmental needs (e.g., Play that enhances socialization, autonomy, cohesion, calmness, and trust.); and
 * 5) Keep open communication lines about what their child is seeing, learning, and doing, and how those things are affecting them.

Parenting skills are widely thought to be naturally present in parents; however, there is substantial evidence to the contrary. Those who come from a negative or vulnerable childhood environment frequently (and often unintentionally) mimic their parents' behavior during interactions with their own children. Parents with an inadequate understanding of developmental milestones may also demonstrate problematic parenting. Parenting practices are of particular importance during marital transitions like separation, divorce, and remarriage; if children fail to adequately adjust to these changes, they are at risk of negative outcomes (e.g. increased rule-breaking behavior, problems with peer relationships, and increased emotional difficulties).

Research classifies competence and skills required in parenting as follows:
 * Parent-child relationship skills: quality time spent, positive communications, and delighted show of affection.
 * Encouraging desirable behavior: praise and encouragement, nonverbal attention, facilitating engaging activities.
 * Teaching skills and behaviors: being a good example, incidental teaching, human communication of the skill with role-playing and other methods, communicating logical incentives and consequences.
 * Managing misbehavior: establishing firm ground rules and limits, directing discussion, providing clear and calm instructions, communicating and enforcing appropriate consequences, using restrictive tactics like quiet time and time out with an authoritative stance rather than an authoritarian one.
 * Anticipating and planning: advanced planning and preparation for readying the child for challenges, finding out engaging and age-appropriate developmental activities, preparing the token economy for self-management practice with guidance, holding follow-up discussions, identifying possible negative developmental trajectories.
 * Self-regulation skills: monitoring behaviors (own and children's), setting developmentally appropriate goals, evaluating strengths and weaknesses and setting practice tasks, monitoring and preventing internalizing and externalizing behaviors.
 * Mood and coping skills: reframing and discouraging unhelpful thoughts (diversions, goal orientation, and mindfulness), stress and tension management (own and children's), developing personal coping statements and plans for high-risk situations, building mutual respect and consideration between members of the family through collaborative activities and rituals.
 * Partner support skills: improving personal communication, giving and receiving constructive feedback and support, avoiding negative family interaction styles, supporting and finding hope in problems for adaptation, leading collaborative problem solving, promoting relationship happiness and cordiality.

Consistency is considered the "backbone" of positive parenting skills and "overprotection" the weakness.

The Arbinger Institute adds to these skills and methods of parenting with what the authors of The Parenting Pyramid claims are methods to "parent for things to go right," or in other words steps that should be taken to ensure good positive relationships are occurring in the home which can help children be more willing to listen. Their methods are described as The Parenting Pyramid. The Parenting Pyramid starting at the foundational level and working up to the top:

 * 1) Ways of being
 * 2) Relationship with spouse
 * 3) Relationship with child
 * 4) Teaching
 * 5) and finally, Corrections

Believing that as parents are focused on this order of establishing their homes and parenting styles, then if a parent has to encourage different behaviors from children this correction will come from a better place and therefore the children may be more receptive to such feedback, compared to if a parent attempts to correct behaviors before focusing on the previous steps.

Parent training
Parent psychosocial health can have a significant impact on the parent-child relationship. Group-based parent training and education programs have proven to be effective at improving short-term psychosocial well-being for parents. There are many different types of training parents can take to support their parenting skills. Some groups include Parent-Child Interaction Therapy (PCIT), Parents Management Training (PMT), Positive Parenting Program (Triple P), The Incredible Years, and Behavioral and Emotional Skills Training (BEST). PCIT works with both parents and children in teaching skills to interact more positively and productive. PMT is focused for children aged 3–13, in which parents are the main trainee. They are taught skills to help deal with challenging behaviors from their children. Triple P focus on equipping parents with the information they need to increase confidence and self-sufficiency in managing their children's behavior. The Incredible Years focuses in age infancy-age 12, in which they are broken into small-group-based training in different areas. BEST introduces effective behavior management techniques in one day rather than over the course of a few weeks. Courses are offered to families based on effective training to support additional needs, behavioral guidelines, communication and many others to give guidance throughout learning how to be a parent.

Cultural values
Parents around the world want what they believe is best for their children. However, parents in different cultures have different ideas of what is best. For example, parents in hunter–gatherer societies or those who survive through subsistence agriculture are likely to promote practical survival skills from a young age. Many such cultures begin teaching children to use sharp tools, including knives, before their first birthdays. In some Indigenous American communities, child work provides children the opportunity to absorb cultural values of collaborative participation and prosocial behavior through observation and activity alongside adults. These communities value respect, participation, and non-interference, the Cherokee principle of respecting autonomy by withholding unsolicited advice. Indigenous American parents also try to encourage curiosity in their children via a permissive parenting style that enables them to explore and learn through observation of the world.

Differences in cultural values cause parents to interpret the same behaviors in different ways. For instance, European Americans prize intellectual understanding, especially in a narrow "book learning" sense, and believe that asking questions is a sign of intelligence. Italian parents value social and emotional competence and believe that curiosity demonstrates good interpersonal skills. Dutch parents, however, value independence, long attention spans, and predictability; in their eyes, asking questions is a negative behavior, signifying a lack of independence.

Even so, parents around the world share specific prosocial behavioral goals for their children. Hispanic parents value respect and emphasize putting family above the individual. Parents in East Asia prize order in the household above all else. In some cases, this gives rise to high levels of psychological control and even manipulation on the part of the head of the household. The Kipsigis people of Kenya value children who are innovative and wield that intelligence responsibly and helpfully—a behavior they call ng/om. Other cultures, such as in Sweden and Spain, value sociality and happiness as well.

Indigenous American cultures
It is common for parents in many Indigenous American communities to use different parenting tools such as storytelling —like myths— Consejos (Spanish for "advice"), educational teasing, nonverbal communication, and observational learning to teach their children important values and life lessons.

Storytelling is a way for Indigenous American children to learn about their identity, community, and cultural history. Indigenous myths and folklore often personify animals and objects, reaffirming the belief that everything possesses a soul and deserves respect. These stories also help preserve the language and are used to reflect certain values or cultural histories.

The Consejo is a narrative form of advice-giving. Rather than directly telling the child what to do in a particular situation, the parent might instead tell a story about a similar situation. The main character in the story is intended to help the child see their decision's implications without directly deciding for them; this teaches the child to be decisive and independent while still providing some guidance.

The playful form of teasing is a parenting method used in some Indigenous American communities to keep children out of danger and guide their behavior. This parenting strategy uses stories, fabrications, or empty threats to guide children in making safe, intelligent decisions. For example, a parent may tell a child that there is a monster that jumps on children's backs if they walk alone at night. This explanation can help keep the child safe because instilling that fear creates greater awareness and lessens the likelihood that they will wander alone into trouble.

In Navajo families, a child's development is partly focused on the importance of "respect" for all things. "Respect" consists of recognizing the significance of one's relationship with other things and people in the world. Children largely learn about this concept via nonverbal communication between parents and other family members. For example, children are initiated at an early age into the practice of an early morning run under any weather conditions. On this run, the community uses humor and laughter with each other, without directly including the child—who may not wish to get up early and run—to encourage the child to participate and become an active member of the community. Parents also promote participation in the morning runs by placing their child in the snow and having them stay longer if they protest.

Indigenous American parents often incorporate children into everyday life, including adult activities, allowing the child to learn through observation. This practice is known as LOPI, Learning by Observing and Pitching In, where children are integrated into all types of mature daily activities and encouraged to observe and contribute in the community. This inclusion as a parenting tool promotes both community participation and learning.

One notable example appears in some Mayan communities: young girls are not permitted around the hearth for an extended period of time, since corn is sacred. Although this is an exception to their cultural preference for incorporating children into activities, including cooking, it is a strong example of observational learning. Mayan girls can only watch their mothers making tortillas for a few minutes at a time, but the sacredness of the activity captures their interest. They will then go and practice their mother's movements on other objects, such as kneading thin pieces of plastic like a tortilla. From this practice, when a girl comes of age, she is able to sit down and make tortillas without having ever received any explicit verbal instruction.

However, in many cases oppressive circumstances such as forced conversion, land loss, and displacement led to diminishment of traditional Native American parenting techniques.

Immigrants in the United States: Ethnic-racial socialization
Due to the increasing racial and ethnic diversity in the United States, ethnic-racial socialization research has gained some attention. Parental ethnic-racial socialization is a way of passing down cultural resources to support children of color's psychosocial wellness. The goals of ethnic-racial socialization are: to pass on a positive view of one's ethnic group and to help children cope with racism. Through a meta-analysis of published research on ethnic-racial socialization, ethnic-racial socialization positively affects psychosocial well-being. This meta-analytic review focuses on research relevant to four indicators of psychosocial skills and how they are influenced by developmental stage, race and ethnicity, research designs, and the differences between parent and child self-reports. The dimensions of ethnic-racial socialization that are considered when looking for correlations with psychosocial skills are cultural socialization, preparation for bias, promotion of mistrust, and egalitarianism.

Ethnic-racial socialization dimensions are defined as follows: cultural socialization is the process of passing down cultural customs, preparation for bias ranges from positive or negative reactions to racism and discrimination, promotion of mistrust conditions synergy when dealing with other races, and egalitarianism puts similarities between races first. Psychosocial competencies are defined as follows: self-perceptions involve perceived beliefs of academic and social capabilities, interpersonal relationships deal with the quality of relationships, externalizing behaviors deal with observable troublesome behavior, and internalizing behavior deals with emotional intelligence regulation. The multiple ways these domains and competencies interact show small correlations between ethnic-racial socialization and psychosocial wellness, but this parenting practice needs further research.

This meta-analysis showed that developmental stages affect how children perceived ethnic-racial socialization. Cultural socialization practices appear to affect children similarly across developmental stages except for preparation for bias and promotion of mistrust which are encouraged for older-aged children. Existing research shows ethnic-racial socialization serves African Americans positively against discrimination. Cross-sectional studies were predicted to have greater effect sizes because correlations are inflated in these kinds of studies. Parental reports of ethnic-racial socialization influence are influenced by "intentions", so child reports tend to be more accurate.

Among other conclusions derived from this meta-analysis, cultural socialization and self-perceptions had a small positive correlation. Cultural socialization and promotion of mistrust had a small negative correlation, and interpersonal relationships positively impacted cultural socialization and preparation for bias. In regard to developmental stages, ethnic-racial socialization had a small but positive correlation with self-perceptions during childhood and early adolescence. Based on study designs, there were no significant differences, meaning that cross-sectional studies and longitudinal studies both showed small positive correlations between ethnic-racial socialization and self-perceptions. Reporter differences between parents and children showed positive correlations between ethnic-racial socialization when associated with internalizing behavior and interpersonal relationships. These two correlations showed a greater effect size with child reports compared to parent reports.

The meta-analysis on previous research shows only correlations, so there is a need for experimental studies that can show causation amongst the different domains and dimensions. Children's behavior and adaptation to this behavior may indicate a bidirectional effect that can also be addressed by an experimental study. There is evidence to show that ethnic-racial socialization can help children of color obtain social-emotional skills that can help them navigate through racism and discrimination, but further research needs to be done to increase the generalizability of existing research.

Pre-pregnancy
Family planning is the decision-making process surrounding whether to become parents or not, and when the right time would be, including planning, preparing, and gathering resources. Prospective parents may assess (among other matters) whether they have access to sufficient financial resources, whether their family situation is stable, and whether they want to undertake the responsibility of raising a child. Worldwide, about 40% of all pregnancies are not planned, and more than 30 million babies are born each year as a result of unplanned pregnancies.

Reproductive health and preconception care affect pregnancy, reproductive success, and the physical and mental health of both mother and child. A woman who is underweight, whether due to poverty, eating disorders, or illness, is less likely to have a healthy pregnancy and give birth to a healthy baby than a woman who is healthy. Similarly, a woman who is obese has a higher risk of difficulties, including gestational diabetes. Other health problems, such as infections and iron-deficiency anemia, can be detected and corrected before conception.

Pregnancy and prenatal parenting

During pregnancy, the unborn child is affected by many decisions made by the parents, particularly choices linked to their lifestyle. The health, activity level, and nutrition available to the mother can affect the child's development before birth. Some mothers, especially in relatively wealthy countries, overeat and spend too much time resting. Other mothers, especially if they are poor or abused, may be overworked and may not be able to eat enough, or may not be able to afford healthful foods with sufficient iron, vitamins, and protein, for the unborn child to develop properly.

Newborns and infants
Newborn parenting is where the responsibilities of parenthood begin. A newborn's basic needs are food, sleep, comfort, and cleaning, which the parent provides. An infant's only form of communication is crying, while there is some argument that infants have different types of cries for being hungry or in pain, that has largely been refuted. Newborns and young infants require feedings every few hours, which is disruptive to adult sleep cycles. They respond enthusiastically to soft stroking, cuddling, and caressing. Gentle rocking back and forth often calms a crying infant, as do massages and warm baths. Newborns may comfort themselves by sucking their thumb or by using a pacifier. The need to suckle is instinctive and allows newborns to feed. Breastfeeding is the recommended method of feeding by all major infant health organizations. If breastfeeding is not possible or desired, bottle feeding is a common alternative. Other alternatives include feeding breastmilk or formula with a cup, spoon, feeding syringe, or nursing supplement.

The forming of attachments is considered the foundation of the infant's capacity to form and conduct relationships throughout life. Attachment is not the same as love or affection, although they often go together. Attachments develop immediately, and a lack of attachment or a seriously disrupted attachment has the potential to cause severe damage to a child's health and well-being. Physically, one may not see symptoms or indications of a disorder, but the child may be affected emotionally. Studies show that children with secure attachments have the ability to form successful relationships, express themselves on an interpersonal basis, and have higher self-esteem. Conversely children who have neglectful or emotionally unavailable caregivers can exhibit behavioral problems such as post-traumatic stress disorder or oppositional defiant disorder. Oppositional-defiant disorder is a pattern of disobedient and rebellious behavior toward authority figures.

Toddlers

Toddlers are small children between 12 and 36 months old who are much more active than infants and become challenged with learning how to do simple tasks by themselves. At this stage, parents are heavily involved in showing the small child how to do things rather than just doing things for them; it is normal for the toddler to mimic the parents. Toddlers need help to build their vocabulary, increase their communication skills, and manage their emotions. Toddlers will also begin to understand social etiquette, such as being polite and taking turns.

Toddlers are very curious about the world around them and are eager to explore it. They seek greater independence and responsibility and may become frustrated when things do not go the way that they want or expect. Tantrums begin at this stage, which is sometimes referred to as the 'Terrible Twos'. Tantrums are often caused by the child's frustration over the particular situation, and are sometimes caused, simply because they are not able to communicate properly. Parents of toddlers are expected to help guide and teach the child, establish basic routines (such as washing hands before meals or brushing teeth before bed), and increase the child's responsibilities. It is also normal for toddlers to be frequently frustrated. It is an essential step to their development. They will learn through experience, trial, and error. This means that they need to experience being frustrated when something does not work for them in order to move on to the next stage. When the toddler is frustrated, they will often misbehave with actions like screaming, hitting or biting. Parents need to be careful when reacting to such behaviors; giving threats or punishments is usually not helpful and might only make the situation worse. Research groups led by Daniel Schechter, Alytia Levendosky, and others have shown that parents with histories of maltreatment and violence exposure often have difficulty helping their toddlers and preschool-age children with the very same emotionally dysregulated behaviors which can remind traumatized parents of their adverse experiences and associated mental states.

Regarding gender differences in parenting, data from the US in 2014 states that, on an average day, among adults living in households with children under age 6, women spent 1.0 hours providing physical care (such as bathing or feeding a child) to household children. By contrast, men spent 23 minutes providing physical care.

Child
Younger children start to become more independent and begin to build friendships. They are able to reason and can make their own decisions in many hypothetical situations. Young children demand constant attention but gradually learn how to deal with boredom and begin to be able to play independently. They enjoy helping and also feeling useful and capable. Parents can assist their children by encouraging social interactions and modeling proper social behaviors. A large part of learning in the early years comes from being involved in activities and household duties. Parents who observe their children in play or join with them in child-driven play have the opportunity to glimpse into their children's world, learn to communicate more effectively with their children, and are given another setting to offer gentle, nurturing guidance. Parents also teach their children health, hygiene, and eating habits through instruction and by example.

Parents are expected to make decisions about their child's education. Parenting styles in this area diverge greatly at this stage, with some parents they choose to become heavily involved in arranging organized activities and early learning programs. Other parents choose to let the child develop with few organized activities.

Children begin to learn responsibility and consequences for their actions with parental assistance. Some parents provide a small allowance that increases with age to help teach children the value of money and how to be responsible.

Parents who are consistent and fair with their discipline, who openly communicate and offer explanations to their children, and who do not neglect the needs of their children in any way often find they have fewer problems with their children as they mature.

When child conduct problems are encountered, behavioral and cognitive-behavioral group-based parenting interventions have been found to be effective at improving child conduct, parenting skills, and parental mental health.

Adolescents
Parents often feel isolated and alone when parenting adolescents. Adolescence can be a time of high risk for children, where newfound freedoms can result in decisions that drastically open up or close off life opportunities. There are also large changes that occur in the brain during adolescence; the emotional center of the brain is now fully developed, but the rational frontal cortex has not matured fully and still is not able to keep all of those emotions in check. Adolescents tend to increase the amount of time spent with peers of the opposite gender; however, they still maintain the amount of time spent with those of the same gender—and do this by decreasing the amount of time spent with their parents.

Although adolescents look to peers and adults outside the family for guidance and models for how to behave, parents can remain influential in their development. Studies have shown that parents can have a significant impact, for instance, on how much teens drink. Other studies show that parents continued presence in provides stability and nurture to their developing adolescents.

During adolescence children begin to form their identity and start to test and develop the interpersonal and occupational roles that they will assume as adults. Therefore, it is important that parents treat them as young adults. Parental issues at this stage of parenting include dealing with rebelliousness related to a greater desire to partake in risky behaviors. In order to prevent risky behaviors, it is important for the parents to build a trusting relationship with their children. This can be achieved through behavioral control, parental monitoring, consistent discipline, parental warmth and support, inductive reasoning, and strong parent-child communication.

When a trusting relationship is built up, adolescents are more likely to approach their parents for help when faced with negative peer pressure. Helping children build a strong foundation will ultimately help them resist negative peer pressure. Not only will a positive relationship between adolescent and parent benefit when faced with peer pressure, it will help with identity-processing in early adolescents. Research by Berzonsky et al. found that adolescents that were open and trusting of their parents were given more freedom and their parents were less likely to track them and control their behavior.

Adults
Parenting does not usually end when a child turns 18. Support may be needed in a child's life well beyond the adolescent years and can continue into middle and later adulthood. Parenting can be a lifelong process. Parents may provide financial support to their adult children, which can also include providing an inheritance after death. The life perspective and wisdom given by a parent can benefit their adult children in their own lives. Becoming a grandparent is another milestone and has many similarities with parenting. Roles can be reversed in some ways when adult children become caregivers to their elderly parents.

Assistance
Parents may receive assistance with caring for their children through child care programs. Article 25.2 of the Universal Declaration of Human Rights declares that: "Motherhood and childhood are entitled to special care and assistance. All children, whether born in or out of wedlock, shall enjoy the same social protection."

Childbearing and happiness
Data from the British Household Panel Survey and the German Socio-Economic Panel suggests that having up to two children increases happiness in the years around the birth, and mostly only for those who have postponed childbearing. However, having a third child is not shown to increase happiness. Data from a private opinion American survey, called Success Index, suggests that parenting is deemed important for people, especially for those aged 65 and older as compared to those aged 18 to 35. According to the survey, being a parent is now an integral part of the new American Dream.

title: Parenting


text:
Tactile illusion

A tactile illusion is an illusion that affects the sense of touch. Some tactile illusions require active touch (e.g., movement of the fingers or hands), whereas others can be evoked passively (e.g., with external stimuli that press against the skin). In recent years, a growing interest among perceptual researchers has led to the discovery of new tactile illusions and to the celebration of tactile illusions in the popular science press. Some tactile illusions are analogous to visual and auditory illusions, suggesting that these sensory systems may process information in similar ways; other tactile illusions don't have obvious visual or auditory analogs.

Passive tactile spatiotemporal illusions
Several tactile illusions are caused by dynamic stimulus sequences that press against the stationary skin surface.

 * One of the best known passive tactile spatiotemporal illusions is the cutaneous rabbit illusion, in which a sequence of taps at two separated skin locations results in the perception that intervening skin regions were also tapped. The rabbit illusion, also called sensory saltation, occurs in vision and audition as well as in touch.
 * The tau effect or perceptual length contraction is an illusion in which equally spaced taps to the skin are perceived as unequally spaced, depending on the timing between the taps. Specifically, a shorter temporal interval between two taps causes the illusion that the taps are closer together spatially. This illusion occurs also in vision and audition.
 * The kappa effect or perceptual time dilation is a complementary illusion to the tau effect: taps separated by equal temporal intervals are perceived to be separated by unequal temporal interval, depending on the spatial intervals between the taps. Specifically, a longer spatial interval between taps causes the illusion that the taps are separated more in time. This illusion occurs also in vision and audition.
 * If a person exposes their forearm and closes their eyes or turns their head in the opposite direction while a second person slowly traces a finger from the wrist upward to the crook of the elbow, many people are unable to say when the crease of their elbow is being touched.
 * One of the least known passive tactile spatiotemporal illusions is the twisted lip illusion, in which a vertical edge touched to the two lips during a grimace is perceived to be tilted in the direction opposite to the skewed lips.

Tactile adaptation illusions
Many illusions in vision are caused by adaptation, the prolonged exposure to a previous stimulus. In such cases, the perception of a subsequent stimulus is altered. This phenomenon is sometimes referred to as a contingent after-effect. Similarly, adaptation can cause such illusions in the sense of touch.

 * If one hand is immersed in cold water and the other in hot for a minute or so, and then both hands are placed in lukewarm water, the lukewarm water will feel hot to the hand previously immersed in cold water, and cold to the hand previously immersed in hot water.
 * If a person is lying on their stomach with arms stretched in front and another person raises their arms about 2 feet off the ground and holds them there for approximately one minute, with the person on the ground having their eyes closed and head hanging, then slowly lowers the arms to the ground, it will feel as if the arms are going below the level of the rest of the body.
 * Focal adaptation evoked by prolonged stimulation to a skin area causes the illusion that two subsequently presented stimulus points straddling that area are farther apart than they actually are. This perceptual repulsion illusion is analogous to various visual repulsion illusions such as visual tilt effects.

Other tactile illusions
It is possible to simulate a string being pulled out of ones hand or knee cap. Requires two people. Touching and tracing motions in the form of star like shapes. Such as an asterisk is drawn with person 2's finger. On person 1. The. After 60 or 90 seconds. The person should pinch. The center and it feels like a string. Is being pulled from the palm, or knee.
 * When eating, if a person holds food with one texture and another texture is presented to the mouth, many people perceive the perceived freshness and crispiness of the food to be between the two textures.
 * When touching paradoxical objects, one can feel a hole when actually touching a bump. These "illusory" objects can be used to create tactile "virtual objects".
 * The thermal grill illusion occurs when one touches the hand down on an interlaced grid of warm and cool bars and experiences the illusion of burning heat.
 * When the thumb and forefinger are slid repeatedly along the edge of a wedge, a rectangular block then handled, in the same manner, will feel deformed.
 * Moving the crossed index and middle finger along an edge evokes the perception of two parallel edges. Similarly, if a person crosses their index and middle finger and then rolls a marble between the tips of the fingers, two marbles are perceived.
 * If a person wears a baseball cap for a long period of time and then takes it off, it may still be felt.
 * If a person turns their tongue upside down, and runs their finger along the front, it will feel like the finger is moving in the opposite direction.
 * If a person pushes outwards with their hands against something for a while, then stops, it will feel as if there is something stopping the person's hands from closing together. Similarly, if a person pulls outwards with their arms, for example pulling their pants outwards, then stops, it will feel as if something is keeping their hands from staying at their sides.
 * After exercising on a treadmill or walking on a moving sidewalk for extended periods, a person will often feel "pulled forward" when they step off onto stationary ground.
 * If two people join their opposite hands and one slides their index and thumb over two joined fingers, they will feel the other finger like it was one of their own.
 * If a person has been in the sea for a long time, they may afterwards still feel the ocean current pushing and pulling them.
 * If a person vigorously spins their relaxed hands in circles around each other and then slowly moves the palms of their hands towards each other, they may feel a sensation akin to magnetic repulsion (or an "invisible ball of energy") between their palms.

title: Tactile illusion


text:
Hospital volunteer

Hospital volunteers, also known as candy stripers in the United States, work without regular pay in a variety of health care settings, usually under the direct supervision of nurses.

The term candy striper is derived from the red-and-white striped pinafores that female volunteers traditionally wore, which are culturally reminiscent of candy canes. The term and its associated uniform are less frequently used in current clinical settings.

Another hospital volunteer organization sponsored by the American Red Cross, was the "Blue Teens" who wore blue-and-white striped pinafores. The female adult volunteers of this organization were known as "Grey Ladies" and wore light grey uniforms.

In the United States, volunteers' services are of considerable importance to individual patients as well as the health care system in general. Some people volunteer during high school or college (and more rarely at the middle school level), out of curiosity about health-care professions, an interest in learning to be of service in a community volunteer organization, or in order to satisfy community service requirements as required by some schools. Additionally, other people choose to volunteer at later stages in their life, particularly after retirement.

History
Candy Stripers originated as a high-school civics class project in East Orange, New Jersey, in 1944. The uniforms were sewn by the girls in the class from material provided by the teacher – a red-and-white-striped fabric known as "candy stripe". The students chose East Orange General Hospital as the home for their class project.

Red Cross pins and patches were also worn on the uniforms indicating completion of required Red Cross training.

Usually a hospital sponsored either Candy Striper or Blue Teen volunteers but not both.

Duties
Duties of hospital volunteers vary widely depending upon the facility. Volunteers may work in staff reception areas and gift shops; file and retrieve documents and mails; take out trash; clean; provide administrative backup; assist with research by following strict sterilizing procedures for laboratory glass and plasticware, known as autoclaving; help visitors; visit with patients; or transport various small items like flowers, medical records, lab specimens, and drugs from unit to unit. Other volunteer tasks include running a music or art therapy program, where volunteers draw or play an instrument for the patients. Some hospitals even utilize volunteers to cuddle newborn babies.

A few hospitals ask their volunteers to help out with janitorial duties, such as stripping and remaking beds with clean linens. Other "advanced volunteers" include patient-care liaisons and volunteer orderlies. These volunteers must operate on the orders of a nurse or a physician and are given special training to permit them to work with patients. They are also more common in large hospitals, particularly university-affiliated hospitals and teaching hospitals, as they allow pre-medical students to gain experience in patient care by taking pressure off a busy care team.

Some hospitals manage their volunteers from a dispersal unit and assign them to tasks based on real-time labor demands, while other hospitals assign volunteers to a single unit for the duration of their service. Female volunteers traditionally wore pink-and-white jumpers, while male volunteers traditionally wore light-blue tunics or shirts over dark slacks. Today, male and female volunteers often wear a uniform shirt, polo shirt or some other short-sleeved shirt with slacks. Some volunteers (particularly "advanced volunteers") will wear scrubs, but this is usually avoided so volunteers are not confused with medical personnel. All volunteers wear ID tags within the hospital that prominently indicate the volunteer's status and position.

title: Hospital volunteer


text:
Dick Whittington (photographer)

Wayne "Dick" Whittington, was a Los Angeles photography studio owner, whose photographic career extended from the 1932 Olympic games, to the first 'wired' photograph transmissions from the Rose Bowl.

Early life
Wayne "Dick" Whittington was a Los Angeles native, and a student at USC. He first established a photography studio in the garage of his house, near the USC campus. Later, after World War II, he located his business premises in downtown Los Angeles.

Career
Whittington founded the Dick Whittington Studio.

"'The 'Dick' Whittington Studio was the largest and finest photography studio in the Los Angeles area from 1924 to 1987.'"

Among Whittington's innovations were the setting up of a mobile laboratory, that made it possible to transmit photographs from a Rose Bowl football game directly to newspapers and wire services. He captured many images of the 1932 summer Olympics, and of the early air races at Mines Field, which is now Los Angeles International Airport. Over his sixty-year career, Whittington and his staff created many millions of negatives; these are now archived at California State University, Long Beach, and the Huntington Library in San Marino.

Personal life
Whittington is survived by his son Edward, three grandchildren, and three great-grandchildren.

Legacy
The Dick Whittington Studio archives are divided between the University of Southern California and the Huntington Library.

title: Dick Whittington (photographer)


text:
Talk:Silver City Airways

Is Silver City an airport or a flight company? Don't get it clear from the article -- JeLuF

Silver City
Silver City also flew out of Blackbush in Surrey in th late forties/early fifties.I remember Blackbush because the hangars and runway were on opposite sides of a main road. The last I heard of Blackbush was about 30 years ago when the runway was being used for drag racing.

I corrected the reference to Broken Hill. As for "Taffy", could he have been Captain Grimth James Powell, ex-Imperial Airways? Grant65 (Talk) 01:04, Feb 8, 2005 (UTC)

 * Correct name is Griffith James Powell - see Lympne Airport article.

 * Talking of which, the moves to Southend and RAF West Malling were only temporary while Lympne was waterlogged. Services returned to Lympne and operated until 1954. Mjroots (talk) 20:38, 5 December 2008 (UTC)

Hurn (Bournemouth) to France (Cherbourg?)
A piece missing here, I think ... I am sure I was a passenger (with parents & car) on subject route in late 50's or early 60's.

 * The article does say In addition to airports mentioned above, the airline also operated air ferries from Southampton, Hurn, etc., to continental destinations. not a lot but it does mention Hurn. MilborneOne (talk)

Airfix Dakota Model
IIRC, sometime when the kit was new Airfix released their 1:72 scale Douglas Dakota with transfers for Silver City livery, with a choice of either Silver City or US military markings. The corresponding model of the Bristol Superfreighter had BUAF markings IIRC. —Preceding unsigned comment added by 86.112.55.67 (talk) 15:56, 26 June 2010 (UTC)

 * Good article. BTW, I may be wrong but IIRC, all of Silver City's "DC-3s" were actually ex-RAF Dakotas.

 * Just a FYI, just about any DC-3/C-47/Dakota was referred to as a 'Dakota' or 'Dak' in the UK back then, and for some strange reason, often a Dakota would be called a "DC-3" incorrectly - the C-47/Dakota all had the enlarged cargo doors on the left of the fuselage, as well as an astrodome on the cabin roof and a truncated tail cone for glider shackles. DC-3's didn't. Many conversions of Dakotas to passenger configuration were carried out by Airwork Services at Gatwick. — Preceding unsigned comment added by 2.24.205.73 (talk) 17:27, 31 August 2014 (UTC)

title: Talk:Silver City Airways