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 (Danbury line to Iron Works District), 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
Comments:Included in a list of minerals without details, but plausible for the geology.
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view U. S. Route 7 Expressway (Danbury line to Iron Works District), Brookfield, Fairfield County, Connecticut, USA
Data Identifiers
Mindat Occurrence Record ID:810499
Long-form Identifier:1:3:810499:1
GUID (UUID V4):0
Nearest other occurrences of Biotite
3.0km (1.8 miles) ⓘAgstone Company Limestone Quarry, Danbury, Fairfield County, Connecticut, USA
4.1km (2.6 miles) ⓘU. S. Route 7 Expressway (Brookfield Bypass), Brookfield, Fairfield County, Connecticut, USA
6.7km (4.2 miles) ⓘNorth Street mall, Danbury, Fairfield County, Connecticut, USA
8.9km (5.5 miles) ⓘOld Quarry Nature Center, 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
10.4km (6.4 miles) ⓘWestern Connecticut State University, Danbury, Fairfield County, Connecticut, USA
14.1km (8.8 miles) ⓘRockside Quarry, Mine Hill, Roxbury, Litchfield County, Connecticut, USA
16.3km (10.1 miles) ⓘNew England Materials quarry, Monroe, Fairfield County, Connecticut, USA
17.1km (10.7 miles) ⓘQuartz mine (Judd's Bridge kyanite locality), Washington, Litchfield County, Connecticut, USA
17.4km (10.8 miles) ⓘRedding Glen, Redding, Fairfield County, Connecticut, USA
References
Januzzi, Ronald. E. (1994) Mineral Data Book - Western Connecticut and Environs. Mineralogical Press, Danbury, Connecticut, USA.
 
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