Adularescence
Optical effect exhibited on particular minerals and gemstones where they display a billowy, ghost-like reflection with a bluish-whitish color emanating through the surface. This effect is caused by structural anomalies or an accumulation of water within the mineral. Opal and Moonstone are the most adularescent that is well-known. The name comes through the variety that is feldspar of, of which Moonstone belongs to.
