Gem labs that comply with CIBJO Blue Books

 

CIBJO Congress 2025 releases Seventh Special Report  

With fewer than four weeks to go to the opening of the 2025 CIBJO Congress in Paris, France, on October 27, 2025, the seventh of the pre-congress Special Reports has been released. Prepared by the CIBJO Gemmological Commission, headed by Hanco Zwaan, the report considers the possibility of CIBJO producing a list of gem laboratories that have committed to applying the standards, principles and nomenclature listed in the CIBJO Blue Books.  

“There have in recent years been concerns expressed about gemstone reports issued by different labs for the same stones, with different and sometime contradictory findings,” writes Dr. Zwaan. “This has brought into question the qualifications of the laboratories issuing the reports, taking into consideration that, worldwide, there is very little official oversight as to what are the requirements for an organisation to claim to be a gem testing laboratory.”

A key document that would have to be applied by listed labs would be the CIBJO Gemmological Laboratories Blue Book, a mammoth opus that is compiled by the Gemmological Commission. Providing guidelines for the management and technical operations of gem labs, it complies with and expands upon ISO Standard 17025, which is the internationally recognised accreditation management systems for testing and calibration laboratories. Also relevant are CIBJO’s Blue Books for diamonds, coloured gemstones, pearls and precious coral.  

“The benefit of such a system is that laboratories with quality management systems in place, which adhere to the clauses and overall content of the CIBJO Gemmological Laboratories Blue Book, can be clearly identified by the trade and consumers alike,” Dr. Zwaan writes. “The system will also encourage openness and transparency in a sphere of operations that has grown significantly in scope over recent decades, where the results given in reports often have significant impact on the value of the item being reported upon.”  

The just-released Gemmology Special Report also looks at the CBJO Jade Guide, which currently is being produced; the work of the Laboratory Manual Harmonisation Committee (LMHC), to which Gemmological Commission members contribute; and growing use of machine-learning and artificial intelligence in the field of gemmology.