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
Cummings Quarry, Georgetown, Sagadahoc County, Maine, 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 Cummings Quarry, Georgetown, Sagadahoc County, Maine, USA
Data Identifiers
Mindat Occurrence Record ID:33675
Long-form Identifier:1:3:33675:6
GUID (UUID V4):0
Nearest other occurrences of Biotite
0.5km (0.3 miles) ⓘTodd's Bay Quarry, Georgetown, Sagadahoc County, Maine, USA
0.7km (0.4 miles) ⓘHoward-Collins Quarry, Georgetown, Sagadahoc County, Maine, USA
0.8km (0.5 miles) ⓘConsolidated Feldspar Quarries, Georgetown, Sagadahoc County, Maine, USA
1.9km (1.2 miles) ⓘPerkins Island beryl locality, Georgetown, Sagadahoc County, Maine, USA
4.0km (2.5 miles) ⓘE. P. Thomas Quarry, Phippsburg, Sagadahoc County, Maine, USA
4.8km (3.0 miles) ⓘParker Head Quarry, Parker Head, Phippsburg, Sagadahoc County, Maine, USA
10.8km (6.7 miles) ⓘSmall Point, Phippsburg, Sagadahoc County, Maine, USA
13.4km (8.4 miles) ⓘDyer Cove, Harpswell, Cumberland County, Maine, USA
17.1km (10.6 miles) ⓘRoute 1 Road Cut, Woolwich, Sagadahoc County, Maine, USA
21.3km (13.3 miles) ⓘPemaquid Point, Bristol, Lincoln County, Maine, USA
References
 
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