Pyroxmangite

Pyroxmangite has the general chemical formula of MnSiO₃.^[5] It is the high-pressure, low-temperature dimorph of rhodonite.^[2]

Pyroxmangite
Pyroxmangite from Chubu Region, Honshu Island, Japan
General
Category	Inosilicate
Formula	MnSiO3
IMA symbol	Pxm[1]
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	5+1⁄2 – 6
Luster	vitreous, pearly
Streak	colorless
Diaphaneity	transparent, translucent
Specific gravity	3.8
Birefringence	δ=0.018
Other characteristics	morphology: tabular crystals, granular massive, grainy
References	[2][3][4]

It was first described in 1913 and named for the mineral group, pyroxenes, and is known as the manganese member.^[6] 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.^[4]