These beautiful 1/4 carat black diamond hoop earrings will be a staple of your wardrobe. Crafted in sterling silver and containing beautiful black diamonds, these hoop earrings are bigger than you might imagine. Get in on this closeout, get a great pair of black diamond earrings and save some money! While natural untreated black diamonds do exist, they are extremely rare. Buy.com sells only heat treated black diamonds, treated with the High Pressure Heat Treatment (HPHT) method. In HPHT treatment, white included poor quality diamonds are heated to approximately 1260 degrees Fahrenheit for a specific length of time, in a reducing atmosphere, meaning under the conditions of very little oxygen, and the unpleasant white and included diamonds become black. We do not sell irradiated black diamonds. HPHT treatment is completely safe, and produces gem quality black diamonds that can be worn an enjoyed for many, many years.