Disclaimer

Last updated 2026-08-26. Please read this before relying on any figure from Gem Index.

Indicative estimates, not appraisals

All figures from Gem Index are indicative trade estimates in US dollars, generated by an automated model from the attributes you enter. They are not a formal appraisal, a certified valuation, or a laboratory certificate, and must not be used as such for insurance, taxation, estate, lending or legal purposes.

The model trusts your inputs

The engine cannot see your stone. It assumes the species, treatment, origin and grades you enter are correct. A misidentified species, an undisclosed treatment, or an over-optimistic colour grade will produce an estimate that does not reflect reality. Synthetic and imitation stones can look identical to natural ones to the unaided eye.

Always confirm with a laboratory

Before buying, selling or insuring a valuable stone, have species, treatment and origin confirmed by an accredited gem laboratory (such as GIA, SSEF, Gübelin, AGL or GRS) and, where needed, obtain a professional appraisal. The cost of a report is trivial next to the price swing it can reveal.

Markets move

Coloured-gem prices vary with supply, fashion and negotiation. Two identical-looking stones can trade at very different prices. Treat the range as a starting point for discussion, not a guaranteed value.

No liability

Gem Index accepts no responsibility for decisions made in reliance on its estimates. See our Terms of Use for the full limitation of liability.