Rainbow Moonstone Cabochon

Size: 32mm L x 12.5mm W x 6.5 D   Hardness 6 - 6.5 

This exquisite rainbow moonstone really glows. It has an extraordinarily beautiful blue shimmer (colorshift) which shines from all directions. Ancient Romans theorized that its earthly shimmer, was formed from frozen moonlight but (sorry to disappoint) it is the mineral feldspar, quite terrestrial in origin. The shimmer, which is called adularescence, is caused by the intergrowth of two different types of feldspar, with different refractive indexes. I still think that is pretty special, just like this specimen! People seem to like moonstone rings but they are a bit soft & will need to be repolished over time.