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
Perkins Island beryl locality, Georgetown, Sagadahoc County, Maine, USA


Locality type:Occurrence
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 Perkins Island beryl locality, Georgetown, Sagadahoc County, Maine, USA
Data Identifiers
Mindat Occurrence Record ID:33660
Long-form Identifier:1:3:33660:4
GUID (UUID V4):0
Nearest other occurrences of Biotite
1.4km (0.9 miles) ⓘTodd's Bay Quarry, Georgetown, Sagadahoc County, Maine, USA
1.8km (1.1 miles) ⓘHoward-Collins Quarry, Georgetown, Sagadahoc County, Maine, USA
1.9km (1.2 miles) ⓘCummings Quarry, Georgetown, Sagadahoc County, Maine, USA
1.9km (1.2 miles) ⓘConsolidated Feldspar Quarries, Georgetown, Sagadahoc County, Maine, USA
3.0km (1.9 miles) ⓘE. P. Thomas Quarry, Phippsburg, Sagadahoc County, Maine, USA
3.5km (2.2 miles) ⓘParker Head Quarry, Parker Head, Phippsburg, Sagadahoc County, Maine, USA
10.5km (6.5 miles) ⓘSmall Point, Phippsburg, Sagadahoc County, Maine, USA
11.6km (7.2 miles) ⓘDyer Cove, Harpswell, Cumberland County, Maine, USA
16.4km (10.2 miles) ⓘRoute 1 Road Cut, Woolwich, Sagadahoc County, Maine, USA
21.6km (13.4 miles) ⓘStandpipe Hill Quarries, Topsham, Sagadahoc County, Maine, USA
References
 
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