Israel Diamond Exchange (IDE) President Yoram Dvash has spoken of his concern following a report by the GIA that even more large HPHT synthetic diamonds are likely to enter the global jewelry industry in the coming years.
The GIA special report spoke about the rapid progress in recent years in High-Pressure, High-Temperature (HPHT) technology being used to produce melee-size diamonds around 2–3 mm in diameter and large colorless single crystals, all with significantly improved quality and growth rate.
A Russian company is reportedly growing many large, gem-quality, colorless diamond crystals in a single run, while large diamond crystals are also being manufactured by a Chinese company using a similar technology, the GIA said.
"There is no doubt that these developments are a concern," Dvash said. "We know the technology for creating these stones is improving all the time and with it the volume of production. There are more such stones entering the market and, with technological abilities becoming so sophisticated, it is becoming increasingly difficult to identify them.
"The main fear is that they might be set, undisclosed, in jewelry as this could cause great damage to consumer confidence where buyers believe they are being sold jewelry set with natural, mined, diamonds. I am sure this issue will be on the agenda of the World Federation of Diamond Bourses (WFDB) at the World Diamond Congress in Dubai in May as it is posing a growing threat to our industry," he added.
GIA officials visited the Chinese factory last month and obtained 50 crystals which were examined using the instrumentation and techniques applied to all diamonds submitted to GIA for grading. Weighing from around 0.5 carat to 1.2 carats, they all exhibited typical characteristics of HPHT growth and were identified as synthetic. They were for the most part colorless, with only a few metallic inclusions observed. According to the manufacturer, large quantities of gem-quality colorless and blue diamonds are produced in the factory, in sizes up to 3.5 carats.
"While the total production volume remains unclear, it is undoubtedly significant, and capacity is likely to expand in the near future," the GIA concluded.