About LMHC

The goal of the Laboratory Manual Harmonisation Committee (LMHC) is to achieve the harmonisation of gemmological report language and thereafter the reviewing and updating of this harmonised report language as used by LMHC members.

The purpose is to create a general philosophy for proper nomenclature and disclosure for gem laboratories as well as to initiate and suggest “preferable” language to be used in the gemstone and pearl trade.

LMHC consists of seven major international gemmological laboratories. These currently include:  CGL, Japan; CISGEM Laboratory, Italy; DSEF German Gem Lab, Germany; Gübelin Gem Lab, Switzerland; GIA Gem Laboratory, USA; the Gem and Jewelry Institute of Thailand (GIT), Thailand; and the Swiss Gemmological Institute SSEF, Switzerland.

LMHC does not maintain formal relationships with special interest groups or trade organizations.


The precursors to the LMHC were the InterGemLab Group (1986) and discussions within GILC (Gemstone Industry & Laboratory Conference of the ICA).

In May of 2001 after a GILC meeting in Basel, Kenneth Scarratt was asked by Roland Naftule and Ronny Totah to form and chair a group of international gem laboratories to harmonize report nomenclature as the feeling was a European based group (InterGemLab) was not enough for the global market. The GILC meeting earlier had requested this formation and that the new group should be (1) exclusively composed of lab representatives, (2) with a limited number of members, (3) working in laboratories operating on the international market.


The initial members in 2001 were: Gübelin Gem Lab, (GIA) Gemological Institute of America, CISGEM, (SSEF) Swiss Gemmological Institute, and AGTA Gemological Testing Center (GTC). The Gemmological Association of all Japan GAAJ-ZENHOKYO and GIT Thailand joined shortly thereafter. These members were selected mainly for their leadership and laboratory capabilities.

Intergemlab London meet
The InterGemLab Group was a precursor to the LMHC. Here a meeting in London in the late 1980s.
The InterGemLab Group was a precursor to the LMHC. Here a meeting in London in the late 1980s.
LMHC New York 2003 17
LMHC meeting in New York in 2003.

LMHC Members


The Laboratory Manual Harmonisation Committee (LMHC) is comprised of representatives from the following gemmological laboratories* located in Europe, USA and Asia.

The LMHC regularly meets to discuss gemmological issues and update or add to the contents of the Information Sheets. The opinions or findings in these documents are based on the state of knowledge at the time of the latest publication and may change as new information becomes available.

* listed in alphabetical order

CGL Laboratory

located in Tokyo, Nagoya, Osaka and Fukuoka in Japan

CISGEM Laboratory

located in Milan, Italy

DSEF German Gem Lab

located in Idar Oberstein, Germany

GIA Laboratory

with 5 locations: Two in the USA (Carlsbad and New York); one in Bangkok, Thailand; one in Tokyo, Japan; one in Hong Kong

Gem and Jewelry Institute of Thailand (GIT)

located in Bangkok, Thailand

Gübelin Gem Lab Ltd

located in Lucerne (Switzerland), Hong Kong and New York.

Swiss Gemmological Institute – SSEF

located in Basel, Switzerland