is a rare borate mineral very similar to Ulexite.
both commonly form as silky, fibrous crystal clusters
and are not easy to distinguish. Hydroboracite gems
are very rare. Most crystals are fibrous and silky and
not suitable for faceting.
most notable occurances of Hydroboracite are: Kohnstein Quarry, Niedersachswerfen, Nordhausen, Harz
Mts, Thuringia, Germany; BigadiÁ Mine, BigadiÁ, Balikesir Province, Marmara
Region, Turkey; Boron Pit, U.S. Borax Mine, Boron, Kramer District, Kern
County, California, USA; and Death Valley, San Bernardino County, California, USA.