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


Locality type:Geothermal Field
Classification
Species:Halotrichite
Formula:Fe2+Al2(SO4)4 · 22H2O
Comments:Reportedly rich in Ni; occurs sparingly.
Colour:yellowish white
Abundance at site:Rare
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Halotrichite data
Locality Data:Click here to view The Geysers, West Mayacmas Mining District, Sonoma County, California, USA
Data Identifiers
Mindat Occurrence Record ID:6010
Long-form Identifier:1:3:6010:3
GUID (UUID V4):0
References
Vonsen, Magnus (1946), Minerals at “The Geysers,” Sonoma County, California: California Division Mines Report 42: 290
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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