PRINCETON, New Jersey — Diamonds have an image of purity and light. They are given as a pledge of love and worn as a symbol of commitment. Yet diamonds have led to gruesome murders, rapes and amputations.

Charles Taylor, a former president of Liberia now facing war crimes charges at a special court in The Hague, is alleged to have used diamonds to fund rebels in Sierra Leone's civil war. The case against Taylor represents only one of several examples in which diamonds have facilitated widespread human rights violations.

When diamonds' role in fueling violent conflict in Africa gained worldwide attention, the diamond industry established the Kimberley Process in order to keep "blood diamonds" out of international trade. The initiative has met with some success, although it has not completely halted trade in diamonds from conflict-torn countries like the Democratic Republic of Congo.