LMHC progress harmonized treatment disclosure

Jun 25, 2025

LMHC illustrativeHolding its 31st meeting in Basel, Switzerland, in May 2025, the Laboratory Manual Harmonisation Committee (LMHC) has reported notable progress in the harmonisation of treatment disclosure on laboratory reports and gemstone nomenclature. LMHC was originally formed in 2001, bringing together 7 major international gemmological laboratories based in America, Asia and Europe.

The LMHC is currently comprised of representatives from the Central Gem Laboratory (CGL), CISGEM Laboratory, DSEF German Gem Lab, Gübelin Gem Lab (GGL), GIA Gem Laboratory, the Gem and Jewelry Institute of Thailand (GIT) and the Swiss Gemmological Institute SSEF. The organisation is not formally connected to any trade organisation.

During the recent meeting in May 2025 hosted by the Swiss Gemmological Institute SSEF, the members of LMHC agreed to slight modifications on a number of their information sheets, which exist to facilitate better communication and understanding among professionals in the industry and which are publicly accessible on the LMHC website since many years.

In addition, the LMHC members discussed recent issues in the trade and agreed to add new information sheets that focus mainly on gemstone nomenclature and testing protocols, to be taken as guidelines for both gemmological laboratories and the gem trade.

These new information sheets will include a harmonized protocol for colour stability testing (of corundum), and information sheets concerning the nomenclature of tanzanite vs. zoisite, cobalt-spinel, and emerald vs. green beryl. The amended and the new information sheets will be published in the coming weeks on the LMHC website.

“This meeting has been very productive. All laboratories represented at LMHC worked in a very constructive atmosphere to agree on harmonized language and guidelines to ensure greater consistency and clarity in gemmological lab reports for the gem trade.” said Dr Michael S. Krzemnicki, host of LMHC, summarising the progress made during the meeting in Basel.

You May Also Like

Facebook Feeds

Cover for Heera Zhaveraat
93,687
Heera Zhaveraat

Heera Zhaveraat

Offical Facebook account of heerazhaveraat.com, homepage for Trade News, Articles and Promotion of D

This message is only visible to admins.
Problem displaying Facebook posts.
Click to show error
Error: No posts available for this Facebook ID

Twitter Feeds

Defined by resolve, discipline and conviction, Rohit Sharma embodies enduring strength. Just like Platinum, his character stands the test of time.

Enduring Platinum. For Men of Character.

Discover the new Men of Character Collection by @men_of_platinum

Platinum that stands the test of time, just like men who evolve while staying true to themselves.

Enduring Platinum. For Men of Character.

Explore the Men of Character Collection by @men_of_platinum .

Confident. Effortless. Unmistakably his own. Anirudh Ravichander makes the enduring strength of Platinum his own.

Enduring Platinum. For Men of Character. For Men of Platinum.

Discover the new collection by @men_of_platinum at a store near you.

Resolve. Discipline. Conviction. Rohit Sharma embodies the enduring strength of Platinum.

Enduring Platinum. For Men of Character. For Men of Platinum.

Explore the new Men of Character Collection by @men_of_platinum

Load More

HZ is the Official Supporter of :

Member Of

Founder Member Of