COLEMANITE (miniature)

Colemanite, with the chemical formula Ca2B6O11·5H2O or alternatively CaB3O4(OH)3·H2O, is a borate mineral typically found in evaporite deposits within alkaline lake environments. This secondary mineral arises from the alteration of borax and ulexite. First identified in 1884 near Furnace Creek in Death Valley, it was named in honor of William Tell Coleman, the proprietor of the Harmony Borax Works where it was discovered. Interestingly, Coleman initially suggested the name "smithite" to recognize his business partner, Francis Marion Smith.