Home > California Borate Minerals – July 22 > MS0969 Hydroboracite

Hydroboracite - Sold


Hydroboracite is a calcium magnesium borate mineral named for its composition (Hess, 1834). The mineral has monoclinic symmetry, and forms subparallel groups of bladed crystals with inclined terminations. This find in Death Valley represents a world class occurrence of the mineral, with individual crystals to 1.6 cm. This is a choice miniature example from the Ordway collection. These came out in the 1970s, and an article appeared in volume 9 (1978) of the Mineralogical Record.