A method for changing the color of a diamond. The method comprises placing the diamond in a substrate holder in a chemical vapor deposition (CVD) equipment. The CVD equipment is maintained at pressures near or below atmospheric pressure. A mixture of gases including hydrogen is introduced inside the CVD equipment. The introduced mixture of gases is energized by using microwave radiation to heat the diamond to temperatures above 1400° C. Then, the diamond is maintained at temperatures above 1400° C. for few seconds to few hours.