In August, GIA announced that it would change its LGDRs – which it has issued since 2006 – to include the same colour and clarity grading system as it uses for natural diamonds. Previously, LGDRs used general descriptive terms.
The new reports also specify the method of manufacture – chemical vapour deposition (CVD) or high-pressure, high-temperature (HPHT) – and include an indication of whether post-growth treatments "may" have been applied.
GIA has also redesigned the LGDRs to visually differentiate them from natural diamond grading reports.
However, CIBJO’s latest Laboratory-Grown Diamond Guidance document categorically states that the term ‘report’ is not appropriate for lab-grown diamonds .
A CIBJO statement dated 13 October 2020 notes, “Care should be taken that the report itself does not infer a similarity between a laboratory-grown diamond and a natural diamond. The report, therefore, is referred to a ‘Laboratory-Grown Diamond Product Specification’ and not a grading report."
Futhermore, the statement notes that "if the 4Cs are used by a laboratory to describe the physical characteristics of laboratory-grown diamonds, the letters ‘LG’ should be placed as a prefix before the 2Cs of colour and clarity."
The guidance document also recommends that the manufacturer, production batch, country of manufacture, and specific post-growth treatment and process information be included – none of which are featured in the GIA LGDRs.
The Laboratory-Grown Diamond Guidance document was developed by a committee of representatives from both the natural and lab-grown diamond sectors, with its primary purpose being to “protect and enhance consumer confidence”.
Other organisations, including HRD Antwerp, American Gem Society Laboratories, Gemological Science International and International Gemological Institute, also offer lab-grown diamond reports.
WATCH GIA'S LAB-GROWN DIAMOND REPORT VIDEO
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