thomsenolite

Century Dictionary and Cyclopedia

1. n. A hydrous fluoride of aluminium, calcium, and sodium, found with pachnolite and cryolite in Greenland, also in Colorado.

Wiktionary

1. n. mineralogy A monoclinic-prismatic mineral containing aluminum, calcium, fluorine, hydrogen, oxygen, and sodium.

GNU Webster's 1913

1. n. (Min.) A fluoride of aluminium, calcium, and sodium occurring with the cryolite of Greenland.