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Biotite from
Marriottsville Quarry, Hernwood, Baltimore County, Maryland, USA


09545870017366313985701.jpg
Phlogopite, etc.

Marriottsville Quarry, Hernwood, Baltimore County, Maryland, USA
09545870017366313985701.jpg
Phlogopite, etc.

Marriottsville Quarry, Hernwood, Baltimore County, Maryland, USA
03559770017272735971602.jpg
Phlogopite, etc.

Marriottsville Quarry, Hernwood, Baltimore County, Maryland, 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 Marriottsville Quarry, Hernwood, Baltimore County, Maryland, USA
Data Identifiers
Mindat Occurrence Record ID:198905
Long-form Identifier:1:3:198905:2
GUID (UUID V4):0
Nearest other occurrences of Biotite
6.8km (4.2 miles) ⓘFrost Quarry, Davis, Howard County, Maryland, USA
8.9km (5.5 miles) ⓘMineral Hill Mine, Louisville, Carroll County, Maryland, USA
12.8km (8.0 miles) ⓘPatapsco Mine (Finksburg Mine; Orchard Mine), Patapsco Mines, Finksburg, Carroll County, Maryland, USA
13.3km (8.3 miles) ⓘEllicott City, Howard County, Maryland, USA
13.3km (8.3 miles) ⓘWeber's Quarry, Ellicott City, Howard County, Maryland, USA
13.8km (8.6 miles) ⓘGaither's Quarry, Baltimore County, Maryland, USA
15.2km (9.4 miles) ⓘMcMahon Quarry (Greenspring Quarry), Pikesville, Baltimore County, Maryland, USA
17.8km (11.1 miles) ⓘStaurolite locality, Rockland, Baltimore County, Maryland, USA
20.0km (12.4 miles) ⓘHilton Quarry, Baltimore City, Maryland, USA
21.4km (13.3 miles) ⓘWright Quarry, Stony Run, Baltimore City, Maryland, USA
References
Bernstein, Lawrence R. (1980) Minerals of the Washington, D.C. Area - Issue 5 of Educational series, Maryland Geological Survey. Department of Natural Resources, Maryland Geological Survey. p.1-148.
 
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