Home > Type Localities I – July 8 > MS0722 Cryolite

Cryolite - Sold


Cryolite is a sodium aluminum fluoride. The mineral has a low refractive index, nearly that of liquid water, so when immersed in water (and the sample is transparent) the mineral seems to disappear. The mineral is named for the Greek words for ice and stone. This is a crystalline surface of cryolite showing many square faces, typical of the pseudocubic from of the mineral. There is also thomsenolite present, mostly coating by tan iron oxides. Cryolite crystals are quite rare, and this is seldom seen example. This specimen comes from Ralph Merrill collection, proprietor of Minerals Unlimited. Purchase includes Merrill's catalog card (and label), accessioned in 1979. Also present is Kryolitselskabet Øresund label.