Then in 1973, scientists of the Soviet Union announced that they had developed a manmade diamond which, while still not hard enough for industrial purposes, could vie with natural diamonds in its color and brilliance.
直到一九七三年，蘇聯科學家宣佈研究成功另一種人造鑽，硬度可達八點五，雖還不能作工業用，但顏色、亮度及完美度均能比美天然鑽石。