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Synthetic diamond: A gem-quality diamond made by artificially simulating the growth environment of natural diamonds. After more than ten years of development, industrial production is becoming more and more mature, and the size of single particles is constantly expanding. In addition to the synthesis of yellow and colorless diamonds, it is also possible to synthesize rare blue and pink diamonds in natural diamonds. Natural diamonds are comparable, even to the full extent of natural diamonds.

The maximum specification of single crystal is 15 carats/grain, and the mass production is 1-3 carats/grain, 3-5 carats/grain, 5--8 carats/grain. More than 5 carats are required for customization.