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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Comstockite

A variety of Melanterite
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Formula:
Fe2+(H2O)6SO4 · H2O
A mineral, (Mg,Cu,Zn)SO4 .5H2 O , containing 5.60% ZnO, 9.40% MgO, 9.00% CuO, and 39.07% H2 O ; from the Comstock Lode, NV.

Synonym of: zinc-magnesia chalcanthite


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Unique IdentifiersHide

Mindat ID:
52800 (as Comstockite)
2633 (as Melanterite)
Long-form identifier:
mindat:1:1:52800:7 (as Comstockite)
mindat:1:1:2633:4 (as Melanterite)

Chemistry of ComstockiteHide

Mindat Formula:
Fe2+(H2O)6SO4 · H2O
Element Weights:
Element% weight
O63.304 %
Fe20.087 %
S11.534 %
H5.076 %

Calculated from ideal end-member formula.
Elements listed:
Fe, H, O, S - search for minerals with similar chemistry

Other InformationHide

Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

Internet Links for ComstockiteHide

References for ComstockiteHide

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