补充一点知识,from Wikipedia:
Blood Diamond:
In relation to diamond trading, blood diamond (also called a converted diamond, conflict diamond, hot diamond or a war diamond) refers to a diamond mined in a war zone and sold to finance an insurgency, invading army's war efforts, or a warlord's activity, usually in Africa.
Conflict-free diamonds:
A conflict-free diamond is a diamond whose profits are not used to fund wars and which is produced and mined under ethical conditions. Only diamonds that are certified and can be traced from the mine to the consumer are conflict-free diamonds. Conflict diamonds are still being sold today into the international diamond market as clean diamonds.