What you may legally call it

There is no mineral labeling law in the sense the other properties have one. There is advertising law, and there is a trade custom that is stricter than the law.

No compositional standard

Nobody defines what may be called a specimen, and there is no grading standard to claim compliance with.

Which means the constraint is the general one: a description must not be deceptive, and in a market of knowledgeable buyers the reputational penalty arrives long before any regulator would.

Species names and trade names

A species name is a factual claim about what the material is, and it can be wrong.

A trade name is a marketing term, frequently invented to make one material sound like a more valuable one. Names that graft a valuable species onto a cheaper material are the classic pattern.

Using a trade name without the actual species beside it is the commonest deceptive practice in this trade, and it is usually done by people repeating what they were told.

Write the species. Put the trade name after it if the market uses one.

Where the FTC guides reach

The FTC's Guides for the Jewelry, Precious Metals, and Pewter Industries govern how gemstones and simulants may be described, including the disclosure of treatments.

They apply squarely to cut and gem material and to anything sold as jewelry.

For rough specimens they are not directly in point, and the expectation they express, say what has been done to it, is the trade custom on the specimen side too.

Which makes them the right standard to work to regardless of whether they technically reach you.

The honest form

Species, variety if relevant, locality at the precision you know, size, condition including damage, and any treatment or repair.

Qualifiers where you have them: "as received", "unverified", "said to be from", "visual identification".

None of that weakens a listing. In a market where everybody has been burned by an over-claimed label, a description that shows its own limits is the one that gets trusted.

References