Prosopite, Thomsonite, Ralstonite from Ivigtut, Greenland
- M Cole (Howie G. collection)
- Feb 2, 2017
- 1 min read
Prosopite can forms as an alteration product in cryolite-bearing pegmatites, either as a primary mineral or as an alteration product of cryolite. Shown under shortwave UV.

