Home > California Borate Minerals – July 22 > MS0955 Probertite

Probertite - Sold

Probertite is a lower hydrate of ulexite, a sodium and calcium borate. Eakle (1929) named in the mineral in honor of Frank H. Probert (1876-1940), Dean of the Mining College, University of California (Berkeley). Probertite is unusual in the Kramer deposit, which is dominated by kernite, borax, and colemanite. This is an attractive radiating gray green example, colored by a minor clay content. A good large example for the locality.