Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite
Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
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Howlite from
Borax Consolidated Company Mines, Borate (Borate Camp), Pacific Mine (Pacific Coast Borax Company properties; Borate; Borate Colemanite Mines; Calico; Old Borate; Pacific Coast Borax Co. workings), Calico, Calico District (Daggett District; Calico-Daggett area), Calico Mts (Calico Hills), San Bernardino County, California, USA


Locality type:Mine
Classification
Species:Howlite
Formula:Ca2B5SiO9(OH)5
Confirmation
Validity:Believed Valid
Associated Minerals:
Associates:Bakerite
Data
Mineral Data:Click here to view Howlite data
Locality Data:Click here to view Borax Consolidated Company Mines, Borate (Borate Camp), Pacific Mine (Pacific Coast Borax Company properties; Borate; Borate Colemanite Mines; Calico; Old Borate; Pacific Coast Borax Co. workings), Calico, Calico District (Daggett District; Calico-Daggett area), Calico Mts (Calico Hills), San Bernardino County, California, USA
Data Identifiers
Mindat Occurrence Record ID:650435
Long-form Identifier:1:3:650435:9
GUID (UUID V4):0
References
Giles, W. B. (1903) Bakerite (a new borosilicate of calcium) and howlite from California. Mineralogical Magazine and Journal of the Mineralogical Society, 13 (62) 353-355 doi:10.1180/minmag.1903.013.62.12
Murdoch, Joseph; Webb, Robert Wallace (1966) Minerals of California, Centennial Volume (1866-1966) - California Division of Mines and Geology, Bulletin 189. California Division of Mines and Geology. 559 pp.
 
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