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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Biotite from
Valhalla, Mount Pleasant, Westchester County, New York, USA


Locality type:Quarry
Classification
Species:'Biotite' (not an IMA approved species)
Formula:K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Valhalla, Mount Pleasant, Westchester County, New York, USA
Data Identifiers
Mindat Occurrence Record ID:81502
Long-form Identifier:1:3:81502:2
GUID (UUID V4):0
Nearest other occurrences of Biotite
11.6km (7.2 miles) ⓘVoorhis Quarry, Greenwich, Fairfield County, Connecticut, USA
12.1km (7.5 miles) ⓘLake Street Quarry, Harrison, Westchester County, New York, USA
12.1km (7.5 miles) ⓘHarrison, Westchester County, New York, USA
16.1km (10.0 miles) ⓘLarchmont, Mamaroneck, Westchester County, New York, USA
16.1km (10.0 miles) ⓘBaylis Quarry (Bayliss Quarry), Bedford, Westchester County, New York, USA
17.2km (10.7 miles) ⓘKinkel Quarry, Bedford, Westchester County, New York, USA
17.3km (10.8 miles) ⓘBedford, Westchester County, New York, USA
24.6km (15.3 miles) ⓘCrugers Emery Mine, Montrose, Cortlandt Township, Westchester County, New York, USA
26.9km (16.7 miles) ⓘTubby Hook occurrences, Manhattan (New York County), New York City, New York, USA
32.1km (19.9 miles) ⓘMc Collum Mine, North Salem, Westchester County, New York, USA
References
Manchester, James G. (1931) The Minerals of New York City and its Environs. Bulletin of the New York Mineralogical Club Vol. 3 (1). New York Mineralogical Clubp.95
 
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