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Biotite from
Hoadley Point Quarries, Guilford, New Haven County, Connecticut, 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 Hoadley Point Quarries, Guilford, New Haven County, Connecticut, USA
Data Identifiers
Mindat Occurrence Record ID:786535
Long-form Identifier:1:3:786535:0
GUID (UUID V4):0
Nearest other occurrences of Biotite
7.2km (4.5 miles) ⓘHungry Hill mineral occurrence, Guilford, New Haven County, Connecticut, USA
18.6km (11.6 miles) ⓘRockland Preserve, Madison, New Haven County, Connecticut, USA
25.5km (15.9 miles) ⓘHaynes Deep River Quarry, Deep River, Middlesex County, Connecticut, USA
27.5km (17.1 miles) ⓘState Route 9 rock cuts, Haddam, Middlesex County, Connecticut, USA
27.7km (17.2 miles) ⓘJohn Salak Quarry, Haddam, Middlesex County, Connecticut, USA
28.0km (17.4 miles) ⓘState Route 9 Interchange 13 - Beaver Meadow Road, Haddam, Middlesex County, Connecticut, USA
29.4km (18.3 miles) ⓘTimms Hill (Tim's Hill; Iolite Hill), Haddam, Middlesex County, Connecticut, USA
30.1km (18.7 miles) ⓘJail Hill Road locality (Jail Hill Quarry), Haddam, Middlesex County, Connecticut, USA
30.4km (18.9 miles) ⓘArnold Granite Quarry (General Brainerd Quarry; Great Hill Quarry; Hazelton Quarry; Haddam Quarry; Brookes Quarry), Haddam, Middlesex County, Connecticut, USA
32.2km (20.0 miles) ⓘArsenic and nickel mine (Nickel Mine Brook), Seymour, New Haven County, Connecticut, USA
References
Schairer, John F. (1931): Minerals of Connecticut. State Geological and Natural History Survey Bulletin 51.
 
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