| moonstone (def. 1). |
[moon-stohn] 
| 1. | Also called precious moonstone. a semitransparent or translucent, opalescent, pearly-blue variety of adularia, used as a gem. |
| 2. | any of several adularescent feldspars, as certain varieties of albite, labradorite, or oligoclase, used as gems. |
| 3. | (not used technically) any milky or girasol stone used as a gem. |
