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Romanechite

Romanèchite
Romanechite.jpg
Romanèchite, from the Marquette County, Michigan, US.
General
Category Oxide minerals
Formula
(repeating unit)
(Ba,H2O)2(Mn+4,Mn+3)5O10
Strunz classification 4.DK.10
Crystal system Monoclinic
Crystal class Prismatic (2/m)
(same H-M symbol)
Space group C2/m
Identification
Mohs scale hardness 6-6.5
Luster Submetallic
Streak Blue-black
References

Romanèchite ((Ba,H2O)2(Mn+4,Mn+3)5O10) is the primary constituent of psilomelane, which is a mixture of minerals. Most psilomelane is not pure romanechite, so it is incorrect to consider them synonyms. Romanèchite is a valuable ore of manganese, which is used in steelmaking. It has a monoclinic crystal structure, a hardness of 6 and a specific gravity of 4.7-5. It is associated with hematite, barite, pyrolusite, quartz and other manganese oxide minerals. It has been found in France, Germany, England, Brazil and various parts of the United States, including Arizona, Virginia and Michigan.


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