Answer: moonstones

AnswerCrossword Clue
MOONSTONESOpalescent gems
MOONSTONESGems with a silvery play of color
MOONSTONESTranslucent gems.
MOONSTONESAstronauts' finds
MOONSTONESCertain Armstrong collections
MOONSTONESHeavenly gems?
moonstonesA pearly white semiprecious stone consisting of alkali feldspar
moonstonesMOONSTONE, a nearly pellucid variety of feldspar, showing pearly or opaline reflections from within