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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Actinolite from
Horseshoe Island Calc-Silicate locality, Winthrop, Kennebec County, Maine, USA


Locality type:Deposit
Classification
Species:Actinolite
Formula:◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Actinolite data
Locality Data:Click here to view Horseshoe Island Calc-Silicate locality, Winthrop, Kennebec County, Maine, USA
Data Identifiers
Mindat Occurrence Record ID:42476
Long-form Identifier:1:3:42476:9
GUID (UUID V4):0
References
 
and/or  
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