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-AN from
Hachijō-jima Island, Hachijō Subprefecture, Tokyo Metropolis, Japan


Locality type:Island
Classification
Species:Opal var: Opal-AN
Formula:SiO2 · nH2O
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Opal-AN data
Locality Data:Click here to view Hachijō-jima Island, Hachijō Subprefecture, Tokyo Metropolis, Japan
Data Identifiers
Mindat Occurrence Record ID:775574
Long-form Identifier:1:3:775574:3
GUID (UUID V4):0
References
field collected by Alfredo Petrov, 12-2011
 
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