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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Opal from
Hale-Walker prospects, Collins Hill, Portland, Middlesex County, Connecticut, USA


Locality type:Prospect
Classification
Species:Opal
Formula:SiO2 · nH2O
Comments:Reference contains only a list with no details, but it is common in all pegmatites in the district.
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Opal data
Locality Data:Click here to view Hale-Walker prospects, Collins Hill, Portland, Middlesex County, Connecticut, USA
Data Identifiers
Mindat Occurrence Record ID:96303
Long-form Identifier:1:3:96303:7
GUID (UUID V4):0
Nearest other occurrences of Opal
0.8km (0.5 miles) ⓘStrickland Quarry, Strickland pegmatite, Collins Hill, Portland, Middlesex County, Connecticut, USA
2.0km (1.2 miles) ⓘPelton's Quarry, Portland, Middlesex County, Connecticut, USA
3.3km (2.0 miles) ⓘGreat Hill cobalt mines, Cobalt, East Hampton, Middlesex County, Connecticut, USA
3.3km (2.1 miles) ⓘRiverside Quarry (Western Quarry), White Rock Mining District, Middletown, Middlesex County, Connecticut, USA
3.6km (2.3 miles) ⓘWhite Rocks Quarry (Consolidated Quarry), White Rock Mining District, Middletown, Middlesex County, Connecticut, USA
3.8km (2.3 miles) ⓘWalden Gem Quarry, Portland, Middlesex County, Connecticut, USA
3.8km (2.4 miles) ⓘGotta-Walden Prospect, Portland, Middlesex County, Connecticut, USA
4.1km (2.6 miles) ⓘNathan Hall Quarry, East Hampton, Middlesex County, Connecticut, USA
4.5km (2.8 miles) ⓘCase Quarries, Portland, Middlesex County, Connecticut, USA
4.9km (3.1 miles) ⓘHale Quarry (Andrews Quarry; Glastonbury Quarry), Portland, Middlesex County, Connecticut, USA
References
Januzzi, Ron E., Seaman, David M. (1976) Mineral Localities of Connecticut and Southeastern New York State and Pegmatite Minerals of the World. The Mineralogical Press, Danbury, Connecticut, USA.
 
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