Virtually every color, shade and hue the mind can imagine, nature has created within a marvelous natural color diamond. The range of color varieties is almost inexhaustible but NCDIA is committed to present, on a continuing basis, the full range of color categories expressed by these wonderful natural creations.
Red diamonds are extremely rare. Basically they are very strongly and deeply colored pink diamonds, with the same cause of color, crystal distortion. This combination is so rare that most jeweler and diamond dealers have never even seen a natural red diamond. They do not get large with the 5.11 carat Moussiaf Red shield being the largest known red.
Purple diamonds are very rare. It is believed that they have a similar cause of color as pink diamonds; crystal distortion. They are most often found in Siberia and are generally small in size. There are no historical or famous purple diamonds. This may be due to their inhospitable location. Purple diamonds larger than 5 carats are extremely rare, and their color rarely reaches the intense and vivid color grades.
Violet diamonds are very rare. The vast majority come from the Argyle mine, the same mine that most strongly colored pink diamonds are found. Their color is related to Hydrogen, but the exact mechanism is as yet unknown. They are often very small and diamonds greater than 1 carat are extremely rare. Their color usually has a gray component, diamonds of a pure violet color represent less than 10% of all violets. The number of intense and vivid violet diamonds mined each year could be counted on one hand.
Olive diamonds are often confused with green diamonds, but they populate a different and discrete area of color space. Their color is a combination of yellow and green sometimes also a bit of brown or gray. They often come with three colors to describe them such as brownish greenish Yellow, and while this does accurately describe the color olive is a simpler, more concise term. They can range is size from small to large (some are 10+ carats). Occasionally they exhibit a color change when heated or left in the dark, these are known as chameleon diamonds.
Natural color black diamonds are rare. Their color is due to dark inclusions within the diamond, usually made up of graphite. It is rare that they are large, but the most famous black diamond, the Black Orloff, is 67.50 carats. Usually they are opaque and much of their beauty is the bright, adamantine luster that reflects light off the surface. Often used as melee in fashion jewelry in combination with colorless diamonds black diamonds are becoming very popular.
Natural color white diamonds are not colorless, but are actually white. This can often cause confusion as the term is used loosely. A pure white diamond has a translucency or even opacity that makes the diamond white. This is often caused by sub-microscopic inclusions. They occasionally exhibit a weak play of color (similar to opals) called opalescence. These are highly prized among conniseurs.
Gray diamonds are often steely in appearance and to an untrained eye may be hard to distinguish from colorless diamonds. When viewed side-by-side the difference is obvious, a gray diamond is darker than a colorless one. Pure gray diamonds are rare and are frequently described as a masculine color diamond.