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Biotite from
Gap Mine, Bart Township, Lancaster County, Pennsylvania, 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 Gap Mine, Bart Township, Lancaster County, Pennsylvania, USA
Data Identifiers
Mindat Occurrence Record ID:976393
Long-form Identifier:1:3:976393:7
GUID (UUID V4):0
Nearest other occurrences of Biotite
17.9km (11.1 miles) ⓘRawlinsville, Martic Township, Lancaster County, Pennsylvania, USA
22.2km (13.8 miles) ⓘCoatesville pegmatite locality, Coatesville, Chester County, Pennsylvania, USA
25.1km (15.6 miles) ⓘSafe Harbor Quarry, Safe Harbor, Conestoga Township, Lancaster County, Pennsylvania, USA
25.3km (15.7 miles) ⓘGoat Hill Barrens, West Nottingham Township, Chester County, Pennsylvania, USA
29.3km (18.2 miles) ⓘGrace Mine, Morgantown, Berks County, Pennsylvania, USA
38.4km (23.9 miles) ⓘDinning Rutile prospect, Clermont Mills, Harford County, Maryland, USA
38.5km (23.9 miles) ⓘCounty Line Quarry, Wrightsville, York County, Pennsylvania, USA
40.0km (24.9 miles) ⓘFrench Creek Mines, Saint Peters, Warwick Township, Chester County, Pennsylvania, USA
41.4km (25.7 miles) ⓘPort Deposit Quarry (Port Deposit Granite Company), Cecil County, Maryland, USA
42.5km (26.4 miles) ⓘBenjamin Franklin Mine, Chester Springs, West Pikeland Township, Chester County, Pennsylvania, USA
References
R. C. Smith II, The Mineralogy of Pennsylvania 1966-1975, Special Publication No. 1, Friends of Mineralogy Pennsylvania Chapter, 1978.
 
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