June 26, 2014 —
Cut and polished howlite specimen(s) from Tick Canyon (Santa Clarita Valley) on display in the Smithsonian National Museum of Natural History
in Washington, D.C.
Howlite — Ca2B5SiO9(OH)5 — is a calcium borosilicate hydroxide (a borate mineral) that
forms when crystals are left behind from an evaporative process. It usually occurs in nodules, as seen here; it can also occur as crystals, which are
quite rare. The crystal form (not seen here) was first discovered in Tick Canyon.
Included in the Smithsonian's display are howlite from Tick Canyon and other
types of borates from the world's primary source of borax: the U.S. Borax (now
Rio Tinto Borax) mine in Boron, Calif. Prior to the name change to Rio Tinto
(and for a little while after), U.S. Borax was headquartered in Valencia.
The museum signage reads:
the U.S. Borax open-pit mine in Boron, California, is one of the world's
largest borax mines. Borax is used in detergents and pottery glazes.
It is also a source of boron — important in making glass, fertilizers,
pesticides, fire retardants, and stealth military hardware.