Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite
Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
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Phlogopite from
Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA


Locality type:Road Cutting
Classification
Species:Phlogopite
Formula:KMg3(AlSi3O10)(OH)2
Comments:Described by Vogt (1991) as brown mica in pegmatite, but much muscovite or annite can appear brown and Mg is very scarce in pegmatites.
Confirmation
Validity:Erroneously Reported
Data
Mineral Data:Click here to view Phlogopite data
Locality Data:Click here to view Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
Data Identifiers
Mindat Occurrence Record ID:657241
Long-form Identifier:1:3:657241:9
GUID (UUID V4):0
Nearest other occurrences of Phlogopite
5.9km (3.7 miles) ⓘWaterbury Road quarry, Thomaston, Litchfield County, Connecticut, USA
33.4km (20.7 miles) ⓘAdvance Stone Quarry, Boardman's Bridge, New Milford, Litchfield County, Connecticut, USA
34.4km (21.4 miles) ⓘColebrook Dam and Colebrook River Lake, Colebrook, Litchfield County, Connecticut, USA
37.5km (23.3 miles) ⓘU. S. Route 7 Expressway (Brookfield Bypass), Brookfield, Fairfield County, Connecticut, USA
38.6km (24.0 miles) ⓘU. S. Route 7 Expressway (Danbury line to Iron Works District), Brookfield, Fairfield County, Connecticut, USA
39.8km (24.7 miles) ⓘRedwing Quarry, Falls Village, Canaan, Litchfield County, Connecticut, USA
40.2km (25.0 miles) ⓘConklin Limestone Company quarry (Falls Village Quarry), Falls Village, Canaan, Litchfield County, Connecticut, USA
40.7km (25.3 miles) ⓘAllyndale Limestone Corp. quarry, East Canaan, North Canaan, Litchfield County, Connecticut, USA
40.7km (25.3 miles) ⓘPfizer Company Marble Quarry, Canaan, North Canaan, Litchfield County, Connecticut, USA
41.3km (25.6 miles) ⓘStrickland Quarry, Strickland pegmatite, Collins Hill, Portland, Middlesex County, Connecticut, USA
References
Vogt, Wolfgang. (1991), Rediscovering Thomaston Dam. Lapidary Journal: April.
 
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