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
Forest of Dean Mine, Fort Montgomery, Town of Highlands, Orange County, New York, USA


Locality type:Mine
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 Forest of Dean Mine, Fort Montgomery, Town of Highlands, Orange County, New York, USA
Data Identifiers
Mindat Occurrence Record ID:83108
Long-form Identifier:1:3:83108:4
GUID (UUID V4):0
Nearest other occurrences of Biotite
6.3km (3.9 miles) ⓘBeechy Bottom Mine, Harriman State Park, Rockland County, New York, USA
7.9km (4.9 miles) ⓘPhilips Mine (Philips Pyrite Mine; Anthony's Nose Pyrrhotite Mine), Town of Philipstown, Putnam County, New York, USA
11.0km (6.9 miles) ⓘGreenwood mine (Patterson mine), Town of Tuxedo, Orange County, New York, USA
11.1km (6.9 miles) ⓘMount Taurus Quarry, Town of Philipstown, Putnam County, New York, USA
11.4km (7.1 miles) ⓘHasenclever Mine, Harriman State Park, Rockland County, New York, USA
11.5km (7.1 miles) ⓘNickel Mine (Bulson lot), Grape Swamp Mountain, Harriman State Park, Rockland County, New York, USA
12.0km (7.4 miles) ⓘVillage of Monroe, Town of Monroe, Orange County, New York, USA
12.4km (7.7 miles) ⓘGreenwood Furnace, Arden (Greenwood), Orange County, New York, USA
13.5km (8.4 miles) ⓘHogencamp Mine, Town of Tuxedo, Orange County, New York, USA
13.7km (8.5 miles) ⓘClove Mine (Wilks Mine), Village of Monroe, Town of Monroe, Orange County, New York, USA
References
Clarke, John M. (1921, September) The Magnetite Iron Deposits of Southeastern New York. New York State Museum Bulletin Vol. 249-250. The University of the State of New YorkIndex Map, 103.
 
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