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Pyroxmangite

Pyroxmangite
Pyroxmangite-261781.jpg
Pyroxmangite from Chubu Region, Honshu Island, Japan
General
Category Inosilicate
Formula
(repeating unit)
MnSiO3
Strunz classification 9.DO.05
Crystal system Triclinic
Crystal class Pinacoidal (1)
(same H-M symbol)
Space group C1
Unit cell a = 9.69 Å, b = 10.5 Å,
c = 17.39 Å; α = 112.17°,
β = 102.85°, γ = 82.93°;
V = 1,596.00 Å³; Z = 28
Identification
Color pink, red, brown
Twinning Lamellar on {010}, simple on {001}
Cleavage Perfect on {110}, {110}, (110) ^ (110) = 92° poor on {010}, {001}
Fracture hackly, uneven
Tenacity brittle
Mohs scale hardness 5½–6
Luster vitreous, pearly
Streak colorless
Diaphaneity transparent, translucent
Specific gravity 3.8
Birefringence δ=0.018
References

Pyroxmangite has the general chemical formula of MnSiO3. It is the high-pressure, low-temperature dimorph of rhodonite.

It was first described in 1913 and named for the mineral group, pyroxenes, and is known as the manganese member. It forms a series with pyroxferroite.

Pyroxmangite occurs in metamorphosed ore deposits rich in manganese. Associated minerals include spessartine, tephroite, alleghanyite, hausmannite, pyrophanite, alabandite, rhodonite and rhodochrosite.



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