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

Polymorphism (materials science)

Polymorphism in materials science is the ability of a solid material to exist in more than one form or crystal structure. Polymorphism can potentially be found in any crystalline material including polymers, minerals, and metals, and is related to allotropy, which refers to chemical elements...

 of rhodonite

Rhodonite

Rhodonite is a manganese inosilicate, SiO3 and member of the pyroxenoid group of minerals, crystallizing in the triclinic system...

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It was first described in 1913 and named for the mineral group, pyroxene

Pyroxene

The pyroxenes are a group of important rock-forming inosilicate minerals found in many igneous and metamorphic rocks. They share a common structure consisting of single chains of silica tetrahedra and they crystallize in the monoclinic and orthorhombic systems...

s, and is known as the manganese

Manganese

Manganese is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature , and in many minerals...

 member. It forms a series with pyroxferroite

Pyroxferroite

Pyroxferroite SiO3 is a silicate mineral of the pyroxene group. It is mostly composed of iron, silicon and oxygen, with smaller fractions of calcium and several other metals. Together with armalcolite and tranquillityite, it is one of the three minerals which were discovered on the Moon. It was...

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Pyroxmangite occurs in metamorphosed

Metamorphism

Metamorphism is the solid-state recrystallization of pre-existing rocks due to changes in physical and chemical conditions, primarily heat, pressure, and the introduction of chemically active fluids. Mineralogical, chemical and crystallographic changes can occur during this process...

 ore deposits rich in manganese. Associated minerals include spessartine

Spessartine

Spessartine previously named spessartite, is a nesosilicate, manganese aluminium garnet species, Mn3Al23.The name is a derivative of Spessart in Bavaria, Germany, the type locality of the mineral. It occurs most often in granite pegmatite and allied rock types and in certain low grade metamorphic...

, tephroite

Tephroite

Tephroite is a non-metallic manganese silicate mineral with the formula, Mn2SiO4.It was first described for an occurrence at the Sterling Hill Mine and Franklin, New Jersey, USA. It occurs in iron-manganese ore deposits and their related skarns. It also occurs in metamorphosed manganese-rich...

, alleghanyite

Alleghanyite

Alleghanyite is a moderately rare humite mineral with formula Mn522, belonging to the nesosilicates class. In general its occurrences are related with metamorphic manganese deposits. The mineral is named after Alleghany County, North Carolina, USA....

, hausmannite

Hausmannite

Hausmannite is a complex oxide of manganese containing both di- and tri-valent manganese. The formula can be represented as Mn2+Mn3+2O4. It belongs to the spinel group and forms tetragonal crystals...

, pyrophanite, alabandite

Alabandite

Alabandite or alabandine is a a rarely occurring manganese sulfide mineral. It crystallizes in the cubic crystal system with the chemical composition Mn2+S and develops commonly massive to granular aggregates, but rarely also cubic or octahedral crystals to 1 cm.- Etymology and History :Alabandite...

, rhodonite

Rhodonite

Rhodonite is a manganese inosilicate, SiO3 and member of the pyroxenoid group of minerals, crystallizing in the triclinic system...

 and rhodochrosite

Rhodochrosite

Rhodochrosite is a manganese carbonate mineral with chemical composition MnCO3. In its pure form, it is typically a rose-red color, but impure specimens can be shades of pink to pale brown. The streak is white. Its Mohs hardness varies between 3.5 and 4. Its specific gravity is 3.5 to 3.7. It...

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