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The Incomparable
The Incomparable is a 407.48-carat faceted, fancy brownish-yellow diamond. It is the world’s third-largest faceted diamond, after the Golden Jubilee and the Cullinan I. It measures 53.90 x 35.19 x 28.18 millimeters in size and is cut into a unique triangular shape named a “triolet.” The diamond ended up in the hands of De Beers…
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The Tiffany Yellow
In 1878 one of the largest yellow diamonds ever found was unearthed at the Kimberley Mine in the North Cape Province of South Africa. The rough diamond weighed 287.42 carats and it was purchased by Charles Tiffany, the New York jeweler who founded the world-famous firm of Tiffany and Company in 1837. Tiffany’s gemologist, George…
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The Design and Color of Settings
When buying a yellow diamond for use in jewelry, the color of the metal used in the setting can be important. The first thing to consider is the contrast or harmony of colors that will be present when the diamond is viewed in the setting. The color of the metal can contrast with the diamond…
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“Capes” and “Canaries”
Two common names used for yellow diamonds are “Capes” and “canaries”. The name “Cape” originated in the late 1800s when many diamonds with an obvious yellow color were being produced from mines in the Cape Province of South Africa. They were quickly noticed in the marketplace by diamond professionals who began calling them “Capes” because of…
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The Role of Nitrogen in Yellow Color
Diamonds are composed of carbon atoms, held tightly together in a crystal lattice by strong covalent bonds. When they are composed of pure carbon and are without inclusions or structural defects, they are colorless. Nitrogen atoms are very small and have the ability to substitute for the carbon atoms in diamond’s crystal structure. Trace amounts of nitrogen…
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Pure Yellow and Modified Yellow
The most desirable color for a yellow diamond is pure yellow. However, most yellow diamonds have at least traces of a secondary color. Greenish yellow and orangy yellow are common modifications of yellow color in diamonds. Although pure yellow is the favorite, many people enjoy the modified colors and are happy to get them at…
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Isn’t Yellow Color a Bad Thing?
Nearly all gem-quality diamonds are graded on a color scale that most highly values the absence of color. The most widely used color scale for grading diamonds is the D-to-Z color-grading scale developed by the Gemological Institute of America (GIA). On the GIA scale, a grade of “D” or “colorless” is the highest grade. Traces…
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What Are Yellow Diamonds?
Yellow diamonds are diamonds that have an obvious yellow bodycolor when viewed in the “face-up” position. The yellow color is usually caused by small amounts of nitrogen contained within the diamond’s crystal structure. Yellow diamonds with a rich, pure yellow color are the world’s most valuable yellow gemstone. Many people consider them to be the most beautiful yellow…
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Use of Jet and Jet Substitutes Today
As a fashionable item, jet declined quickly during the Great Depression when the demand for manufactured goods of all kinds collapsed. It never regained its Victorian popularity and is used infrequently today. Jet is one gem material that has been heavily replaced by look-alikes and imitations. When jet was popular, materials such as black glass and gutta-percha…
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History of Human Use
The most important source of jet has always been the eastern coast of England and Scotland, centered near what is now the community of Whitby. In this area people found small, black, rounded, light-weight stones along the shoreline. They discovered that these stones could easily be fashioned into beads and other objects and could be polished…
