Gemstone specifications

None: untreated, no enhancement
Heat: standard for most sapphires and rubies; well-disclosed and accepted
Diffusion: surface or lattice; disclose explicitly, lowers value
Oil / resin: standard for emeralds; grade as Minor / Moderate / Significant
Beryllium: significant value impact for sapphires; must be disclosed

Gemstone Specifications

Coloured gemstones have very different value drivers from diamonds — origin and treatment can swing value by an order of magnitude.

Sapphire, Ruby, Emerald, Opal, Tanzanite, Tourmaline, Aquamarine, Topaz, Amethyst, Citrine, Garnet, Pearl, or Other.

Weight in carats. For multi-stone pieces, enter total carat weight here and the breakdown in Description.

Country of origin where known. For sapphires this is huge: Kashmir > Burma > Ceylon > Madagascar in typical retail-value terms.

We surface a Geographic Origin picker for sapphires, rubies and emeralds because the market premium is so significant.

GRS, Gübelin, SSEF and AGL are the leading coloured-gem labs. Enter the lab and report number for verifiable provenance.

For pearls, instead of carat use the millimetre size and string length. Track the type (Akoya, South Sea, Tahitian, Freshwater) and lustre grade.