What makes diamonds black?
Some of the sources of color in diamonds are: irradiation (usually by alpha particles), that causes the color in green diamonds; and physical deformation of the diamond crystal known as plastic deformation. Plastic deformation is the cause of color in some brown and perhaps pink and red diamonds. In order of rarity, colorless diamond, by far the most common, is followed by yellow and brown, by far the most common colors, then by blue, green, black, translucent white, pink, violet, orange, purple, and the rarest, red. “Black,” or Carbonado, diamonds are not truly black, but rather contain numerous dark inclusions that give the gems their dark appearance.
