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
Trenton Quarry, Topsham, 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 Trenton Quarry, Topsham, Sagadahoc County, Maine, USA
Data Identifiers
Mindat Occurrence Record ID:29650
Long-form Identifier:1:3:29650:0
GUID (UUID V4):0
Nearest other occurrences of Biotite
0.9km (0.6 miles) ⓘHavey #1 & #2 Quarries, Topsham, Sagadahoc County, Maine, USA
1.0km (0.6 miles) ⓘSquare Pit (Consolidated #4 Quarry), Topsham, Sagadahoc County, Maine, USA
1.1km (0.7 miles) ⓘWilliam Willes #1 Quarry, Topsham, Sagadahoc County, Maine, USA
1.8km (1.1 miles) ⓘFisher Quarry, Topsham, Sagadahoc County, Maine, USA
2.8km (1.7 miles) ⓘTwin Pits Quarry, Cathance River Nature Preserve, Topsham, Sagadahoc County, Maine, USA
2.9km (1.8 miles) ⓘSwamp #1 Quarry, Cathance River Nature Preserve, Topsham, Sagadahoc County, Maine, USA
2.9km (1.8 miles) ⓘSwamp #2 quarry, Cathance River Nature Preserve, Topsham, Sagadahoc County, Maine, USA
3.1km (2.0 miles) ⓘConsolidated #2 Quarry (Purington Quarry), Highland Green, Topsham, Sagadahoc County, Maine, USA
3.2km (2.0 miles) ⓘConsolidated #1 Quarry, Highland Green, Topsham, Sagadahoc County, Maine, USA
3.2km (2.0 miles) ⓘAdderton Prospect, Bowdoinham, Sagadahoc County, Maine, USA
References
Bastin, E. S. (1911) Geology of the pegmatites and associated rocks of Maine, including feldspar, quartz, mica, and gem deposits. Bulletin 445. US Geological Survey doi:10.3133/b445
Thompson, Woodrow B., Joyner, Ronald L., Woodman, Raymond G., King, Vandall T. (1998) Bulletin (41), A Collector's Guide to Maine Mineral Localities (3rd ed.) Maine Geological Survey
 
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