The name moonstone is given to feldspars that display a moonlight like glow on their surface called adularescence. The word comes from the mineral adularia, named after Mount Adula in Switzerland. It is produced by the diffraction of light off microscopic layers of alternating orthoclase and albite feldspars.
Romans believed the stone was formed on earth by the light of the moon. Known as the stone of love, fertility, intuition, magic, protection, hope, and spiritual purity. For centuries it has been believed to enhance fertility and support women's reproductive system all around, from easing cramps to assisting women in child birth.