- a semitransparent or translucent, opalescent, pearly-blue variety of adularia, used as a gem.
- any of several adularescent feldspars, as certain varieties of albite, labradorite, or oligoclase, used as gems.
- (not used technically) any milky or girasol stone used as a gem.
- a gem variety of orthoclase or albite that is white and translucent with bluish reflections
