Formula: Fe2+SiO3
Inosilicate (chain silicate), forms a series with pyroxmangite, paramorph of clinoferrosilite, ferrosilite and hemleyite
Specific gravity:
Hardness: 4½ to 5½
Streak: White
Colour: Pale yellow, orange-yellow, yellow, light brown
Solubility: Insoluble in acids
Common impurities: Ti,Al,Mg,Na



The type locality is the Mare Tranquillitatis (Sea of Tranquility), on the Moon. The mineral occurs as discrete grains in rocks collected by the Apollo XI mission. The rocks are microgabbros or dolerites with major clinopyroxene, plagioclase and ilmenite, and with minor pyroxferroite, cristobalite, tridymite, fayalite, fluorapatite and K-feldspar (AM 55.2137).

It also occurs at several localities in Earth as detailed in (Mindat).

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