Home > California Borate Minerals – July 22 > MS0951 Tunellite

Tunellite - Sold

Tunellite is a rare hydrated strontium borate. The mineral is stable in humid and dry environments and not very water soluble. Erd et al. (1961) named tunellite in honor of George Tunell (1900-1996), professor of mineralogy at the University of California at Los Angeles. Tunellite has monoclinic symmetry and perfect cleavage on {001}; the faces of which display pearly luster. This is a large example, showing minor incipent cleavage. This material comes from 1998, when mine geologist Jo Siefke found these crystals. The crystals show extensive parallel growth, serrating some edges and leading to a rougher general appearance. A very large and complete example from the recent find. Excellent!