Very pure diamonds and perfectly perfect chemically transparent without hue, or colors . However, in reality there is almost no gem of a jewel-sized gem that is truly perfect. The diamond color may be affected by chemical impurities and/or structural defects in the crystal lattice. Depending on the color and intensity of the diamond color, the color of the diamond can reduce or increase its value. For example, most white diamonds discounted prices when yellow is more detectable, while intense pink diamonds or blue diamonds (such as Diamond Hope) can be dramatically more valuable. Of all colored diamonds, red diamonds are the rarest. Aurora Pyramid of Hope features a spectacular array of spectacular natural diamonds, including red diamonds.
Video Diamond color
Possible colors
Diamonds occur in different colors - steel gray, white, blue, yellow, orange, red, green, pink into purple, brown, and black. Colored diamonds contain interstitial impurities or structural defects that cause staining, while pure diamonds are highly transparent and colorless. Diamonds are scientifically classified into two main types and some subtypes, according to the nature of the impurities present and how these impurities influence light absorption:
Type I diamonds have a nitrogen atom as the main impurity, generally at a concentration of 0.1%. If their paired nitrogen atoms do not affect the color of the diamond; this is Type IaA. If the atoms of nitrogen are in large quantities of even aggregates, they give a yellow to brown color (Type IaB). Approximately 98% diamond gems are Ia type, and most are a mixture of IaA and IaB materials: these diamonds are included in the Cape series, named after the diamond-rich region formerly known as the Cape Province in South Africa, which most of the sediment is Type Ia. If the nitrogen atoms are dispersed throughout the crystals in isolated places (not paired or grouped), they give intense yellow or sometimes brown color yellow > (Ib type); rare diamond walnut belonging to this species, representing only 0.1% of known natural diamonds. Synthetic diamonds containing nitrogen are Type Ib. Type I diamonds absorb both in the infrared and ultraviolet regions, from 320Ã, nm (3.2 ÃÆ' - 10 -7 m). They also have typical fluorescence and visible absorption spectra (see Optical properties of diamonds).
Type II diamonds have no measurable nitrogen impurities. Type II diamonds absorb in different regions of the infrared, and transmit in ultraviolet below 225 nm (2.25 ÃÆ' - 10 -7 m), unlike diamond Type I They also have different fluorescence characteristics, but no absorption spectrum is visible. Type IIa diamonds can be stained pink , red , or brown due to structural anomalies that arise through plastic deformation during the crystal growth - this diamond is rare (1.8% of gem gems), but represents a large percentage of Australian production. The diamond type IIb, which produces 0.1% gem gems, is usually blue because boron is scattered within the crystal matrix; The diamond is also semiconductor, unlike other diamond types (see the diamond electrical properties). However, the blue-gray color can also occur in Type Ia diamond and is not associated with boron. Also unlimited for typing is a green diamond, whose color is caused by the center of the GR1 color in the crystal lattice generated by exposure to varying amounts of radiation.
Pink and red are caused by the crystal lattice plastic deformation of temperature and pressure. Black diamonds are caused by microscopic black or gray inclusions of other materials such as graphite or sulfide and/or microscopic fractures. Dark or opalescent white diamonds are also caused by microscopic inclusions. Purple diamonds are caused by a combination of distortion of lattice crystals and high hydrogen content.
Maps Diamond color
Grading white diamond
The majority of mined diamonds are in the range of pale yellow or brown color called the normal color range . Diamonds are yellow or brown, or other colors are called fancy colors diamonds. The diamonds that have the highest purity are completely colorless, and look bright white. The level that indicates the diamond body color is one of the four value factors that are rated diamonds. Diamonds have a color scoring system that refers to the absence of color. This system runs from D to Z. The more colorless the diamond, the rarer and more valuable because it looks white and bright for the eyes.
Color rating history
The diamond gradation color is done as a sort of rough diamond sorting for sale by London Diamond Syndicate.
When diamond trading was developed, initial class diamonds were introduced by various parties in diamond trading. Without cooperative development, this initial assessment system does not have standard nomenclature and consistency. Some initial assessment scales are; I , II , III ; A , AA , AAA ; A , B , C . Many terms are developed to illustrate specific diamonds of color: golconda , river , comedians , head , blue white , fine white , blue gems , chocolate , etc.
Grading normal color range
Refers to the rating scale for diamonds within the normal color range used by internationally recognized laboratories (eg GIA & IGI). The scale ranges from D which is completely colorless to Z which is pale yellow or brown. Darker brown diamonds of the K color are usually described using their letter values, and descriptive phrases, for example M Faint Brown . Diamonds with deeper colors than Z colors fall into the luxurious diamond color range.
The diamond color is assessed by comparing stone samples with diamond stone stones . Each parent is known to have the least body color so that the diamond in the color class can show. A trained diamond grader compares diamonds with unknown grade to a series of parent stones , assessing where in the diamond color range is. This process occurs in the lighting box, equipped with the same lights during the day. Accurate color grading can only be done with diamond unset, as the comparison with parent stone is done by diamond placed on the table surface and the side of the pavilion facing up (ie "upside down" - based on the normally seen face). When the color gradation is done in the installation, the value is expressed as the estimated color value and generally as the color range. Grading mount diamonds involve holding a diamond table mounted near the table facet of the master stone and visually comparing the color of the diamond under the same color conditions as the uncoupled diamond grading. The resulting value is usually less accurate, and therefore expressed as various colors. While the assessment laboratory will have a complete set of parent stones representing each color grade, independent grade students working in retail environments work with smaller subsets of mains that only cover the color range is typical of the color they expect to encounter when assessing. The general subset of the master stones will consist of five diamonds with two grade enhancements, such as E , G , I , < i> K , and M . The middle value is assessed by the grader rating.
Diamonds within the normal color range are considered loose (eg F-G).
Grading color of luxury diamond
Colors of yellow or brown diamonds that have a more intense color than "Z", as well as diamonds that show off colors other than yellow or brown are considered luxurious colored diamonds. This diamond is assessed using a separate system that shows the color characteristics, and not just its presence. The color scoring system is more similar to that used for other colored gemstones, such as ruby, sapphire, or emerald, compared to systems used for white diamonds.
Color diamond rating system
The color of the diamond is more saturated than the scale is known as the "luxurious color" diamond. Any bright color diamond other than Light Yellow or Light Brown automatically falls off the scale. For example, pale blue diamonds will not get the color value "K", "N", or "S", it will get the Blue color, Blue Very Light or Blue Light.
The lab uses a list of 27 color colors that reach the full spectrum for gems and colored diamonds (Red, Orangish-Red, Reddish-Orange, orange, Yellow-Orange, Yellow-Orange, Orange-Yellow, Yellow Orangish, Yellow, Green -Yellow, Green - Yellow, Green-Green, Yellow-Green, Green, Green-Bluish, Blue-Green, Green-Blue, Greenish Blue, Blue, Purple- Blue, Purple- Purple, Purple, Purple, Red-Purple, Red-Purple, Purple-Red, Purplish-Red). Modified color combinations can also be added (for example, Olive or Brown-Olive) to stones without pure color. In addition, for the following diamond colors are used: White (milky ones), Black (opaque ones), Gray, Pink, Brown.
The color saturation is then described with one of nine descriptors: Samar, Very Light, Light, Luxurious Light, Fancy, Dark Fancy, Fancy Intense, Fancy Deep, Fancy Vivid.
The terms "Champagne", "Cognac" and "Coffee" refer to different types of brown diamonds. In the diamond processing/processing industry, the word "Brown" is considered a killer as far as incoming diamond values. Although the champagne is light yellow, the diamond champagne is Light Brown. Cognac is usually used to describe diamonds that are Orangish-Brown because cognac is a deep golden-orange color. Coffee is usually used to describe diamonds that are the color of Deep Brown or Vivid Brown. Some grading agencies can also describe brown stones as Fancy Yellowish-Brown, Fancy Light Brown, Fancy Intense Brown, etc.
Colored diamond values ​​
The diamonds in the Gemological Institute of America scale are valued for their clarity and color. For example, diamonds "D" or "E" (both colorless) are far more valuable than "R" or "Y" diamonds (yellow or brown). This is due to two effects: high-colored diamonds are less common, limiting supply; and the bright white appearance of a high-color diamond is more desirable to consumers, increasing demand. Bad colors are usually not enough to eliminate the use of diamonds as gems: if other gemological characteristics of good stones, low color diamonds can remain more valuable as diamond gems than industrial-use diamonds, and can see the use in diamond jewelry. In addition, it is far more effective to buy a diamond that is virtually colorless (eg "G" is valued) instead of a colorless diamond grade (eg "D" is valued), as they are virtually indistinguishable from the naked eye, especially when installed in settings ring.
Diamond luxury is appreciated using different criteria than those used for ordinary diamonds. When the color is rare, the color of the diamond is more intense is, the more valuable the color. Another factor that affects the value of Fancy-Colored diamonds is fashion trends. For example, pink diamonds are priced higher after Jennifer Lopez receives a pink diamond engagement ring. The use of traditional industries and inferior quality does not stop creative merchants, like Le Vian, from marketing dark-brown diamonds as so-called "brown diamonds".
Colorful diamonds like the blue Diamond Diamond are one of the most precious and sought-after diamonds in the world. In 2009, a 7 carat blue diamond (1.4 g) was taken then the highest price per carat ever paid for diamonds when it was sold at auction for 10.5 million Swiss francs (US $ 9.5 million at the time) that exceeded the US $ 1.3 million per carat. The record was broken in 2013 when orange diamonds sold for US $ 35 million or US $ 2.4 million per carat. It was again damaged in 2016 when Oppenheimer Blue, a living 14.62-carat blue diamond (2,924 g) became the most expensive gem ever sold at auction. This is a very large and luxurious blue diamond classified by the American Gemological Institute that was once sold at auction; it was sold at Christie's in Geneva in May 2016 for US $ 50.6 million. The record was broken again by a pink star diamond On April 3, 2017, the Pink Star was sold at an auction in Hong Kong for $ 71.2 million (553 million Hong Kong dollars including fee) for Chow Tai Fook Enterprises. (GBP 34.7m; 56.83 m SFr).
See also
- Clarity of diamond
- Diamond Improvement
References
Further reading
- "Grading Color" D-to-Z 'Diamonds at GIA ". Gems & amp; Gemology , Winter 2008, Vol. 44, No. 4. Detailed history and methodology of GIA color scales.
- Wise, Richard W. (2016). Secret of Trades of Gems, Connoisseur Guides for Precious Gems (Second Edition). Brunswick House Press. pp.Ã, 145-162. ISBN: 9780972822329.
Source of the article : Wikipedia
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