GemsVerified
Laboratory record

Stone Group Labs

A trade-only laboratory used in the United States for coloured stone testing and diamond verification.

The record

HeadquartersUnited States
Founded1999
Kind of bodyReport issuer
Country-of-origin opinionsNot stated
StatusIssuing reports

What it covers

DiamondColoured stone

Worth knowing

Founded in 1999 by Bear and Cara Williams. The current site names no report products and gives no address, so no city is recorded. It lists instrumentation including ED-XRF, FTIR, Raman and UV-Vis-NIR and describes these as aiding geographic origin work, but it does not state that the laboratory issues country-of-origin opinions. Report queries go through an enquiry form rather than an online lookup.

Official sources

Compiled from stonegrouplabs.com, read on August 16, 2026.

We verify dealers, not stones. A laboratory report describes one stone on one date; it is not a guarantee of value, and it is not ours to stand behind.

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