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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Muscovite from
Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA


Locality type:Road Cutting
Classification
Species:Muscovite
Formula:KAl2(AlSi3O10)(OH)2
Formation:Primary
Comments:Major constituent of the schist, and an accessory up to 5 cm in the pegmatites and granite.
Habit:anhedral flakes in schist
Colour:silvery-white
Quality for species:Rock forming mineral/non-crystalline/little interest for collectors.(##)
Abundance at site:Extremely common
Confirmation
Validity:Confirmed
Confirmation Methods:Visually Identified
Associated Minerals Based on Photo Data:
Quartz1
Kyanite1
Data
Mineral Data:Click here to view Muscovite data
Locality Data:Click here to view Thomaston Dam railroad cut, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
Data Identifiers
Mindat Occurrence Record ID:96374
Long-form Identifier:1:3:96374:5
GUID (UUID V4):0
Nearest other occurrences of Muscovite
0.8km (0.5 miles) ⓘThomaston Dam pegmatite, Thomaston Dam, Thomaston, Litchfield County, Connecticut, USA
2.8km (1.7 miles) ⓘLead Mine Brook, Harwinton, Litchfield County, Connecticut, USA
5.0km (3.1 miles) ⓘReynolds Bridge, Thomaston, Litchfield County, Connecticut, USA
5.9km (3.7 miles) ⓘWaterbury Road quarry, Thomaston, Litchfield County, Connecticut, USA
7.1km (4.4 miles) ⓘMorris Dam Quarry (East Morris Dam), Morris, Litchfield County, Connecticut, USA
7.7km (4.8 miles) ⓘState Routes 8 and 118 interchange, Harwinton, Litchfield County, Connecticut, USA
7.8km (4.9 miles) ⓘPegmatite quarry and ultramafic rock, Harwinton, Litchfield County, Connecticut, USA
10.3km (6.4 miles) ⓘSouth Main Street construction site, Torrington, Litchfield County, Connecticut, USA
10.7km (6.7 miles) ⓘState Route 8 interchange 34 (formerly 37), Watertown, Litchfield County, Connecticut, USA
11.2km (7.0 miles) ⓘBlue Stone Quarry, Waterbury, New Haven County, Connecticut, USA
References
Rocks & Minerals: 34: 3.
Zodac, Peter (1959) Minerals at Thomaston Dam, Conn. Rocks & Minerals, 34 (1) 3-48 doi:10.1080/00357529.1959.11766706
Vogt, Wolfgang. (1991), Rediscovering Thomaston Dam. Lapidary Journal: April.
 
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