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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Pyrolusite from
Strickland Quarry, Strickland pegmatite, Collins Hill, Portland, Middlesex County, Connecticut, USA


Locality type:Quarry
Classification
Species:Pyrolusite
Formula:Mn4+O2
Comments:No pyrolusite dendrite or staining in a granite pegmatite in the world has been verified as pyrolusite. The name was a mistake in the nineteenth century which has been widely publicized. See "manganese oxides" for description.
Confirmation
Validity:Erroneously Reported
Data
Mineral Data:Click here to view Pyrolusite data
Locality Data:Click here to view Strickland Quarry, Strickland pegmatite, Collins Hill, Portland, Middlesex County, Connecticut, USA
Data Identifiers
Mindat Occurrence Record ID:96233
Long-form Identifier:1:3:96233:9
GUID (UUID V4):0
Nearest other occurrences of Pyrolusite
3.0km (1.8 miles) ⓘWalden Gem Quarry, Portland, Middlesex County, Connecticut, USA
3.8km (2.3 miles) ⓘState Forest Quarry No. 2, Cobalt, East Hampton, Middlesex County, Connecticut, USA
3.8km (2.3 miles) ⓘCase Quarries, Portland, Middlesex County, Connecticut, USA
3.8km (2.4 miles) ⓘGreat Hill cobalt mines, Cobalt, East Hampton, Middlesex County, Connecticut, USA
4.1km (2.6 miles) ⓘHale Quarry (Andrews Quarry; Glastonbury Quarry), Portland, Middlesex County, Connecticut, USA
4.4km (2.7 miles) ⓘAndrews Quarry (old Hale Quarry; Grandfather Andrews Quarry), Portland, Middlesex County, Connecticut, USA
4.4km (2.7 miles) ⓘWhite Rock Mining District, Middletown, Middlesex County, Connecticut, USA
5.3km (3.3 miles) ⓘHowe Quarry (Howe #1 Quarry; Huspband Quarry), South Glastonbury, Glastonbury, Hartford County, Connecticut, USA
5.4km (3.3 miles) ⓘSimpson Quarry (Wiarda Quarry), South Glastonbury, Glastonbury, Hartford County, Connecticut, USA
6.0km (3.7 miles) ⓘHusband Quarries, South Glastonbury, Glastonbury, Hartford County, Connecticut, USA
References
Schooner, Richard (1955) 90 Minerals from 1 Connecticut Hill. Rocks & Minerals, 30 (7-8). 351-358 doi:10.1080/00357529.1955.11767837
 
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