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
Case Quarries, Portland, Middlesex County, Connecticut, USA


Locality type:Quarry
Classification
Species:Opal
Formula:SiO2 · nH2O
Comments:see Opal-AN variety.
Confirmation
Validity:Confirmed
Confirmation Methods:Visual (Fluorescence)
Data
Mineral Data:Click here to view Opal data
Locality Data:Click here to view Case Quarries, Portland, Middlesex County, Connecticut, USA
Data Identifiers
Mindat Occurrence Record ID:37872
Long-form Identifier:1:3:37872:5
GUID (UUID V4):0
Nearest other occurrences of Opal
1.3km (0.8 miles) ⓘGotta-Walden Prospect, Portland, Middlesex County, Connecticut, USA
1.5km (0.9 miles) ⓘWalden Gem Quarry, Portland, Middlesex County, Connecticut, USA
1.5km (0.9 miles) ⓘHale Quarry (Andrews Quarry; Glastonbury Quarry), Portland, Middlesex County, Connecticut, USA
1.9km (1.2 miles) ⓘSimpson prospect #1, South Glastonbury, Glastonbury, Hartford County, Connecticut, USA
2.1km (1.3 miles) ⓘSimpson Quarry (Wiarda Quarry), South Glastonbury, Glastonbury, Hartford County, Connecticut, USA
2.2km (1.4 miles) ⓘHollister prospects, South Glastonbury, Glastonbury, Hartford County, Connecticut, USA
2.3km (1.4 miles) ⓘHowe Quarry (Howe #1 Quarry; Huspband Quarry), South Glastonbury, Glastonbury, Hartford County, Connecticut, USA
2.7km (1.7 miles) ⓘPelton's Quarry, Portland, Middlesex County, Connecticut, USA
2.8km (1.8 miles) ⓘEureka Quarries, South Glastonbury, Glastonbury, Hartford County, Connecticut, USA
3.8km (2.3 miles) ⓘStrickland Quarry, Strickland pegmatite, Collins Hill, Portland, Middlesex County, Connecticut, USA
References
Jones, Robert W. Jr., (1960), Luminescent Minerals of Connecticut, A Guide to Their Properties and Locations. Fluorescent House. Branford, Connecticut.
 
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