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
U. S. Route 7 Expressway (Brookfield Bypass), Brookfield, Fairfield County, Connecticut, USA


Locality type:Road Cutting
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 U. S. Route 7 Expressway (Brookfield Bypass), Brookfield, Fairfield County, Connecticut, USA
Data Identifiers
Mindat Occurrence Record ID:474115
Long-form Identifier:1:3:474115:2
GUID (UUID V4):0
Nearest other occurrences of Biotite
4.1km (2.6 miles) ⓘU. S. Route 7 Expressway (Danbury line to Iron Works District), Brookfield, Fairfield County, Connecticut, USA
6.3km (3.9 miles) ⓘAgstone Company Limestone Quarry, Danbury, Fairfield County, Connecticut, USA
8.7km (5.4 miles) ⓘNorth Street mall, Danbury, Fairfield County, Connecticut, USA
9.9km (6.1 miles) ⓘGreen's Farm locality (Roxbury garnet mine; Roxbury Falls garnet mine; Garnet Hill), Roxbury, Litchfield County, Connecticut, USA
11.7km (7.3 miles) ⓘRockside Quarry, Mine Hill, Roxbury, Litchfield County, Connecticut, USA
11.8km (7.3 miles) ⓘWestern Connecticut State University, Danbury, Fairfield County, Connecticut, USA
12.0km (7.5 miles) ⓘOld Quarry Nature Center, Danbury, Fairfield County, Connecticut, USA
14.4km (9.0 miles) ⓘQuartz mine (Judd's Bridge kyanite locality), Washington, Litchfield County, Connecticut, USA
18.5km (11.5 miles) ⓘInterstate 84 road cuts, Town of Southeast, Putnam County, New York, USA
20.2km (12.5 miles) ⓘNew England Materials quarry, Monroe, Fairfield County, Connecticut, USA
References
Specimens found and identified by Jeremy Zolan
 
and/or  
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