Orprase

Orprase, was the Realms name for pollucite, a medium-hard, brittle, colorless or faintly straw-yellow gemstone.

Description
These semi-precious stones were found as clear areas in otherwise uninteresting rock samples and was favored by followers of Tymora, presumably because it took luck to find them. Orprase produced small to medium size faceted gems. A typical specimen had a base value of 50 gp.