PROBERTITE FOR SALE

Probertite is a rare, colorless to gray hydrous sodium calcium borate mineral found in evaporite deposits, named for UC mining dean Frank Probert. It's known for its needle-like crystals in radiating rosettes, a hardness of 3.5, and association with borax deposits in places like California and Turkey. It's an important ore of boron, used in glass, fiberglass, soaps, and more, though it's uncommon for collectors.