With fewer than six weeks to go to the opening of the 2025 CIBJO Congress in Paris, France, on October 27, 2025, the fifth of the pre-congress Special Reports has been released. Prepared by the CIBJO Coloured Stones Commission, headed by Charles Abouchar, the report focuses on two material specific-guides – for opal and jade – that currently are being prepared, as well as addressing the impact of U.S. import tariffs on the coloured gemstone sector and the correct descriptive terminology for synthetic stones.

The Opal Guide, which has been worked on since the CIBJO Congress in Bangkok in 2017, outlines classification criteria for all opal varieties, treatment categories and disclosure requirements, and provides standardised terminology to ensure consistency across markets.

The Jade Guide, which originally was initiated to reconcile the terminology, identification and grading of jade in relation to the Fei Cui nomenclature used in East Asia, has focused on harmonising trade names and grading systems for global clarity, balancing China’s four-decade-old, tradition-based standards with the Western gemmological benchmarks widely used by laboratories.

Concluding the report, Mr. Abouchar reported on the Coloured Stone Commission’s intention to propose that “synthetic” once again be used exclusively to describe those manufactured gemstones that match their natural counterparts – in chemical composition, physical properties and structure.

“We have felt that the descriptive terms ‘laboratory-grown’ and ‘laboratory-created’ lack precise definition and could be misapplied to any laboratory-produced substance, including glass or novel composites with no natural equivalent. Furthermore, these materials are manufactured in industrial facilities — not research laboratories — making the terms misleading,” he wrote.