A colored gemstone specification should tell the designer, buyer and production partner what material is intended and which characteristics matter to the project. “Blue stone” or “green gemstone” may communicate a color direction, but it is not a complete material description.

Identify the gemstone

Use the correct gem material name and variety where relevant, such as corundum for ruby or sapphire, beryl for emerald, or quartz for amethyst. Similar colors can occur in different materials, so do not identify a stone from appearance alone.

If the stone is natural, laboratory-grown or a simulant, state that clearly. These categories are not interchangeable.

Record dimensions and shape

For a setting, measurements in millimeters are often essential. Record length, width and depth where appropriate, along with the outline shape and cutting style. Carat weight can also be useful, but it does not replace dimensions. Two stones of the same weight can have different face-up sizes and proportions.

Describe color carefully

Color descriptions may include hue, tone and saturation. Terms such as “royal blue,” “vivid green” or “pastel pink” can help communicate a direction, but they should be accompanied by a visual reference or, where needed, a more formal assessment. Lighting and photography can change perceived color.

When matching multiple stones, state whether exact matching is required or whether a coordinated range is acceptable.

Disclose treatments and enhancements

Some gemstones are routinely treated to improve color, clarity or stability. Common treatments may include heating, dyeing, diffusion, filling, irradiation or impregnation, depending on the material. Their permanence, care implications and effect on value vary.

The FTC consumer guide to buying gemstones explains why buyers should ask about treatments. CIBJO provides industry terminology resources through its Blue Books and guidelines.

Do not write “untreated” unless that claim is supported. If treatment is unknown, record it as unconfirmed.

Use origin claims carefully

A geographic origin claim can be commercially significant for some gemstones, but it may require specialist laboratory assessment. Do not infer origin from a seller's verbal statement or a photograph. If origin is a requirement, specify the report or evidence needed and who will verify it.

A colored gemstone specification template

  • Gem material and variety.
  • Natural / laboratory-grown / imitation status.
  • Shape and cutting style.
  • Dimensions and carat weight, if available.
  • Color reference or acceptable range.
  • Treatment information and disclosure.
  • Geographic origin claim, only where supported.
  • Laboratory report or supplier documentation, if required.

Frequently asked questions

Can a photograph confirm a colored gemstone's identity? No. Photographs communicate appearance but cannot reliably determine gem species, treatments or geographic origin.

Should all colored gemstones have a laboratory report? Not every project requires one. Decide based on the stone, value, claims, buyer requirements and the consequences of an incorrect identification.

Is carat weight enough to specify a colored stone? No. Dimensions and shape are also important for fit and appearance.

Specify stones before sampling

If a design depends on a particular color or size, make that requirement clear before the setting is finalized. Discuss gemstone options with VELORA MUSE and identify which facts need independent confirmation.