A variety of albite, feldspar, showing pearly or opaline reflections from within. Gray with blue iridescence, apricot with white iridescence, rainbow with blue, green, pink and yellow irridescence. The best stones come from Sri Lanka. It derives its name from its resemblance in luster to the moon. Mohs 6 - 6.5.
Moonstone protects from harm and danger.
Brings good fortune, especially in love matters. Arouses the tender passions. Women should not wear this stone during the time of the full moon or when menstruating. Moonstone is very cooling in fever if applied to both temples. Antagonistic to the solar plexus.