section_path: Materials and methods/Diamonds
section_name: Diamonds
paragraph_text: Diamonds
  
  Diamonds were first mined in India. Pliny may have mentioned them, although there is some debate as to the exact nature of the stone he referred to as Adamas. In 2005, Australia, Botswana, Russia and Canada ranked among the primary sources of gemstone diamond production. There are negative consequences of the diamond trade in certain areas. Diamonds mined during the recent civil wars in Angola, Ivory Coast, Sierra Leone, and other nations have been labeled as blood diamonds when they are mined in a war zone and sold to finance an insurgency.
  
  The British crown jewels contain the Cullinan Diamond, part of the largest gem-quality rough diamond ever found (1905), at 3,106.75 carats (621.35 g).
  
  Now popular in engagement rings, this usage dates back to the marriage of Maximilian I to Mary of Burgundy in 1477.
  
  A popular style is the diamond solitaire, which features a single large diamond mounted prominently. Within solitaire, there are three categories in which a ring can be classified: prong, bezel and tension setting.