Mineralpedia Details for Ralstonite
Named for Reverend J. Grier Ralston of Pennsylvania, USA, who was the first to observe the mineral. It occurs in granite pegmatites that are fluorine bearing as well as in antimony deposits of hydrothermal origin within silicified limestone. Quite a few localities including in Greenland, the USA, Bolivia, Australia, Norway, Italy, Ukraine, Kazakhstan, Russia, and others.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/ralstonite.pdf
Ralstonite from Ivigtut Cryolite deposit, Ivigtut, Arsuk Fjord, Sermersooq, Greenland
Colorless, but stained by iron, octahedral crystals of Ralstonite to 2mm.