Laboratory
Goldsmiths' Company Assay Office
London, United Kingdom
Precious metal testing and hallmarking
The Goldsmiths' Company Assay Office in London has hallmarked precious metals since 1300, one of the oldest forms of consumer protection in the world; its mark is the leopard's head. It works at Goldsmiths' Hall and in Hatton Garden.
What it does
Testing and hallmarking of gold, silver, platinum and palladium, laser marking, and analytical services.
Using any laboratory
- Ask what the report will state (identity, treatment, origin, grade) and how long it takes; turnaround and fees change.
- Check a report online with the laboratory's own report-check service, and match the stone to the report.
- Reports from different laboratories can differ, especially on colour grades, treatment and origin. A report is an opinion based on the tests made, not a valuation.
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