Squeezing Sapphire: The Heat+ Pressure Treatment of Sapphire

Barbra Voltaire, FGG · **Posted:** Wed Feb 27, 2019 1:46 pm

Quote:

Introduction
Sapphires heated with high temperatures and low pressures first entered the market in 2009, becoming more common since 2016. In late 2018, one well-known lab issued a study claiming that such stones had durability issues. This was quickly followed up by a press release from a major trade association stating that they would require separate disclosure of any sapphires treated with heat and pressure.

We believe the central question is not simply one of disclosure (all labs disclose the stones as treated), but if the changes produced by the HT+P treatment are something beyond what one could do with traditional heating.

This article is a rare example of labs around the world sharing research and ideas. It reviews both the trade and lab history of treatment disclosure, followed by a detailed examination of the high-temperature heat + pressure treatment of sapphire, including questions of durability.

The central question is whether or not the addition of modest pressure to the heat treatment process deserves separate disclosure to traders and consumers. Click on the following link or image to learn more:
Squeezing Sapphire: Corundums treated with high temperatures and low pressures (HT+P)

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