International bodies and standards
Laboratory Manual Harmonisation Committee (LMHC)
Gem laboratories agreeing common wording for coloured stone reports
The Laboratory Manual Harmonisation Committee (LMHC) is a group of leading gem laboratories that agree common wording for coloured stone reports.
What it does
Publishes information sheets with standard terms for treatments and descriptions, so reports from different labs say the same thing in the same way.
Why it matters to you
It explains why reports use particular wording, for example for heating or clarity enhancement.
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