Black diamonds are the latest in the jewelry trend. Though they are nothing like what we usually associate Diamonds with -neither white or transparent, nor do they sparkle, but Black Diamonds exist naturally and are real diamonds. Their stunning appearance has charmed celebrities and designers alike. Mysterious dark color, smooth luster and the realistic price is what pulls everyone towards them. However Black diamonds are very different from the regular diamonds.
Black diamonds like the regular white diamonds are crystallized carbon. However they are black and polycrystalline therefore also called Carbonados. Each black diamond is made of multiple micro-crystals that have vacancies so when light falls on the diamond it gets absorbed causing the diamond not to sparkle. Since black diamonds do not sparkle they are evaluated on the basis of the clear surface, luster and color.
The color of the black diamonds is due to the numerous dark inclusions and factures that have stained due to the high temperatures. Typically gray, dark gray, dark green or brown, very-very rarely one comes across a rich black diamond. Even the finest quality natural black diamonds have a metallic blackish dark green or deep brown color. However for the diamond to be graded high, it is imperative for the color to spread uniformly across the stone.
Natural black diamonds that have not been treated radiated or heated are a rarity and are thus very expensive. Moreover natural black diamonds above 1.00 carat without surface or visible inclusions are even rarer. Untreated- unheated natural black diamonds are typically opaque, with high luster and a metallic appearance. GIA does the grading of only natural untreated black diamonds.
Treated/enhanced -though most of the black diamonds available in the market today have been treated/enhanced but they are still 100% natural. The treatment is either to enhance the color or improve the clarity of the diamonds. The treatment usually involves heating or irradiating the gray or dull green real diamonds to get a rich black color. Treated or not as long as the diamond has uniformly rich color and does not show any inclusions on the surface it’s a great diamond.