Diamond

The mineral diamond is a crystalline form of carbon.  Diamonds are  renowned for their superlative physical qualities, especially their  hardness and their dispersion of white light into a rainbow of colors,  known in the trade as fire, for which they have been highly prized  throughout history.  Industrially, diamonds are ideal material for  cutting and grinding tools  common applications include the cutting  surfaces of saw blades and drill bits.  The De Beers Group has been the
largest player in the diamond industry for over one hundred years.  The  company own mines that produce some 40 percent of annual world diamond  production, and control distribution channels handling nearly two  thirds of all gem diamonds.  Some controversy over diamonds has been  generated because of the monopolistic practices historically employed  by De Beers including strict control of supply and alleged price  manipulation, as well as the practice by some African revolutionary  groups of selling conflict diamonds in order to fund their often  violent activities.

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