0.871CT D VVS HPHT lab diamonds Cushion loose synthetic diamonds

About Diamond Tester

 As HPHT method involves using metal catalyst, it is hard to avoid some metals entering the crystal during growing process, so HPHT diamonds might be magnetic. And if the magnetism is too strong, diamonds will not be able to pass the diamond teste. Because CVD diamonds are formed by mere gas, they can be produced without magnetic and are able to pass the diamond tester pen.