Carlsbad, Calif. – The Gemological Institute of America said it expects even more large lab-grown diamonds produced using the high-pressure, high-temperature (HPHT) method to enter the supply pipeline in the future.
In an article slated to appear in the spring 2016 issue of Gems & Gemology and published on GIA.edu now, the GIA’s Tom Moses and Wuyi Wang described their experience at Jinan Zhongwu New Materials Co. Ltd., a diamond-growing factory in Shandong, China. The GIA asked and, subsequently, was granted permission to visit this factory.
There, Moses, the GIA’s chief laboratory and research officer, and Wang, the director of research and development, obtained 50 crystals ranging in size from 0.5 to 1.2 carats. All were readily identifiable as synthetic using the same instrumentation and techniques applied to diamonds submitted to the GIA for grading, the lab said.
The article also noted that the HPHT technology used to grow gem-quality diamonds has improved rapidly in the last few years, and that it’s now being used to produce “many” melee-size diamond as well as large colorless single crystals.