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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Sassolite from
The Geysers, West Mayacmas Mining District, Sonoma County, California, USA


Locality type:Geothermal Field
Classification
Species:Sassolite
Formula:H3BO3
Comments:One specimen of tiny, transparent flakes.
Habit:Tiny transparent flakes
Abundance at site:Very Rare
Confirmation
Validity:Believed Valid
Associated Minerals:
Associates:Boussingaultite
Mascagnite
Data
Mineral Data:Click here to view Sassolite data
Locality Data:Click here to view The Geysers, West Mayacmas Mining District, Sonoma County, California, USA
Data Identifiers
Mindat Occurrence Record ID:9763
Long-form Identifier:1:3:9763:5
GUID (UUID V4):0
Nearest other occurrences of Sassolite
12.8km (7.9 miles) ⓘSeigler Springs, Cobb, East Mayacmas Mining District, Lake County, California, USA
25.4km (15.8 miles) ⓘSulphur Bank Mine (Sulfur Bank Mine; Sulphur Bank deposits), Clear Lake Oaks, Sulphur Creek Mining District (Sulfur Creek Mining District; Wilbur Springs Mining District), Lake County, California, USA
References
Smith, R. L. (1958) Some new occurrences of sassolite in the United States. American Mineralogist, 43 (11-12). 1204-1205
Pemberton, H. Earl (1983) Minerals of California. Van Nostrand Reinhold Company Inc.
Cooper, Joseph F., Dunning, Gail E. (1993) History and Minerals of The Geysers, Sonoma County, California. The Mineralogical Record, 24 (5) 339-354
 
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