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


Locality type:Quarry
Classification
Species:Grossular
Formula:Ca3Al2(SiO4)3
Comments:A component of the calc-silicate units in the host Collins Hill Formation, with diopside, and a dark green amphibole (described by Schooner as actinolite, but one specimen analyzed by TEM-EDS has proven to be magnesio-hornblende).
Habit:massive
Colour:orange
Quality for species:Poor for species, only of interest for locality collectors. (#)
Confirmation
Validity:Believed Valid
Associated Minerals Based on Photo Data:
Magnesio-hornblende2
Rutile2
Data
Mineral Data:Click here to view Grossular data
Locality Data:Click here to view Strickland Quarry, Strickland pegmatite, Collins Hill, Portland, Middlesex County, Connecticut, USA
Data Identifiers
Mindat Occurrence Record ID:96204
Long-form Identifier:1:3:96204:7
GUID (UUID V4):0
Nearest other occurrences of Grossular
0.1km (0.1 miles) ⓘSchoonmaker Mine, Strickland pegmatite, Collins Hill, Portland, Middlesex County, Connecticut, USA
0.7km (0.5 miles) ⓘCarr Brook Waterfall, Collins Hill, Portland, Middlesex County, Connecticut, USA
3.8km (2.4 miles) ⓘGreat Hill cobalt mines, Cobalt, East Hampton, Middlesex County, Connecticut, USA
4.3km (2.7 miles) ⓘWhite Rocks Quarry (Consolidated Quarry), White Rock Mining District, Middletown, Middlesex County, Connecticut, USA
4.4km (2.7 miles) ⓘWhite Rock Mining District, Middletown, Middlesex County, Connecticut, USA
8.7km (5.4 miles) ⓘWorth and Selden Quarries (Victoria Quarry), East Hampton, Middlesex County, Connecticut, USA
10.2km (6.4 miles) ⓘAnderson No. 1 Mica Mine, East Hampton, Middlesex County, Connecticut, USA
12.0km (7.5 miles) ⓘSlocum prospect, East Hampton, Middlesex County, Connecticut, USA
13.0km (8.1 miles) ⓘGillette Quarry (J-J Mine; Haddam Neck Quarry), Haddam Neck, Haddam, Middlesex County, Connecticut, USA
14.1km (8.8 miles) ⓘHazen quarry (Epidote locality), Haddam, Middlesex 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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