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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Thulite from
Hunting Hill Quarry, Rockville, Montgomery County, Maryland, USA


Locality type:Quarry
Classification
Species:Zoisite var: Thulite
Formula:{Ca2}{Al,Mn33+}(Si2O7)(SiO4)O(OH)
Comments:ACTINOLITE.
ALBITE. (Reported by J. Griesbach, 1975).
ANTHOPHYLLITE. Creamy gray veinlets in serpentinite float.
ANTIGORITE. (G. T. Faust, 1967). Constitutes bulk of serpentinite as interlocking microscopic laths and plates or as tough, brittle, dark
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Thulite data
Locality Data:Click here to view Hunting Hill Quarry, Rockville, Montgomery County, Maryland, USA
Data Identifiers
Mindat Occurrence Record ID:36810
Long-form Identifier:1:3:36810:8
GUID (UUID V4):0
Nearest other occurrences of Thulite
58.9km (36.6 miles) ⓘWright Quarry, Stony Run, Baltimore City, Maryland, USA
References
Jack Nelson, Compiler from two references and personal communications, May 2000 (See descriptive notes for quarry for reference citations)>
 
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