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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Cummingtonite from
Pine Flat Road area, Bonny Doon, Santa Cruz County, California, USA


Locality type:Area
Classification
Species:Cummingtonite
Formula:◻Mg2Mg5(Si8O22)(OH)2
Comments:Occurs as microscopic patches and fibrous, radiating aggregates in the gabbro.
Colour:Colorless
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Cummingtonite data
Locality Data:Click here to view Pine Flat Road area, Bonny Doon, Santa Cruz County, California, USA
Data Identifiers
Mindat Occurrence Record ID:645351
Long-form Identifier:1:3:645351:0
GUID (UUID V4):0
References
Leo, G.W. (1967) The plutonic and metamorphic rocks of the Ben Lomond Mountain area, Santa Cruz County, California. California Division of Mines and Geology Special Report 91: 34
Pemberton, H. Earl (1983) Minerals of California. Van Nostrand Reinhold Company Inc.
 
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