Roughly forty nine% of diamonds originate from Central and Southern Africa , though necessary sources of the mineral have been discovered in Canada , India , Russia , Brazil , and Australia 108 They are mined from kimberlite and lamproite volcanic pipes, which could carry diamond crystals, originating from deep throughout the Earth the place extreme pressures and temperatures permit them to type, to the floor. The mining and distribution of natural diamonds are subjects of frequent controversy corresponding to considerations over the sale of blood diamonds or battle diamonds by African paramilitary groups. 114 The diamond supply chain is …