Vote for your favorite mineral in #MinCup26! - Quartz vs. Asagiite
It's a classic vs a newbie as the most common named mineral in the crust Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago Asagiite.
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Biotite from
Rockside Quarry, Mine Hill, Roxbury, Litchfield 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
Comments:rock-forming mineral
Habit:anhedral
Colour:black
Quality for species:Rock forming mineral/non-crystalline/little interest for collectors.(##)
Abundance at site:Very common
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Rockside Quarry, Mine Hill, Roxbury, Litchfield County, Connecticut, USA
Data Identifiers
Mindat Occurrence Record ID:132111
Long-form Identifier:1:3:132111:1
GUID (UUID V4):0
Nearest other occurrences of Biotite
3.1km (1.9 miles) ⓘQuartz mine (Judd's Bridge kyanite locality), Washington, Litchfield County, Connecticut, USA
7.7km (4.8 miles) ⓘGreen's Farm locality (Roxbury garnet mine; Roxbury Falls garnet mine; Garnet Hill), Roxbury, Litchfield County, Connecticut, USA
11.7km (7.3 miles) ⓘU. S. Route 7 Expressway (Brookfield Bypass), Brookfield, Fairfield County, Connecticut, USA
12.2km (7.6 miles) ⓘNonnewaug River Industrial Park, Woodbury, Litchfield County, Connecticut, USA
14.1km (8.8 miles) ⓘU. S. Route 7 Expressway (Danbury line to Iron Works District), Brookfield, Fairfield County, Connecticut, USA
17.1km (10.6 miles) ⓘAgstone Company Limestone Quarry, Danbury, Fairfield County, Connecticut, USA
19.1km (11.9 miles) ⓘCurtis Quarry, Southford, Southbury, New Haven County, Connecticut, USA
19.7km (12.3 miles) ⓘMount Prospect complex (Prospect Hill complex; Prospect Mountain complex), Litchfield, Litchfield County, Connecticut, USA
20.2km (12.6 miles) ⓘNorth Street mall, Danbury, Fairfield County, Connecticut, USA
22.0km (13.7 miles) ⓘRoute 73 quarry, Waterbury, New Haven County, Connecticut, USA
References
Dale and Gregory (1911)
 
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