16 C.F.R. § 23.26 – Misrepresentation as to varietal name.

(a) It is unfair or deceptive to mark or describe an industry product with the incorrect varietal name.
(b) The following are examples of markings or descriptions that may be misleading:
1. (1) Use of the term “yellow emerald” to describe golden beryl or heliodor.
2. (2) Use of the term “green amethyst” to describe prasiolite.

Note to § 23.26: A varietal name is given for a division of gem species or genus based on a color, type of optical phenomenon, or other distinguishing characteristic of appearance.