This sample is about 4 cm. The chemical formula for hedenbergite is CaFeSi2O6. Hedenbergite is a rock forming mineral in several metamorphic rocks. It is also f — Photo: Shannon Heinle · CC0
Hedenbergite
The iron end-member of the diopside-hedenbergite pyroxene series — a calcium-iron silicate of skarns.
Intro adapted from Wikipedia (CC BY-SA).
Hedenbergite is an IMA-recognized mineral species in the silicate class, with the chemical formula CaFe²⁺Si₂O₆.
It crystallizes in the monoclinic crystal system (space group C2/c). It is a member of the Pyroxene structural group.
Key properties: Mohs hardness 5.5–6.5; specific gravity 3.56; typically green or brown or black; greenish-white streak; Vitreous or dull luster; refractive index 1.729; optically biaxial.
IMA symbol Hd, IMA status: approved, named in 1819.
A common constituent of metamorphosed iron formations or other ferruginous siliceous sediments; common in Fe-Mn skarns. In alkalic granites, syenites, and in xenoliths in kimberlite.
It is found associated with Grunerite (iron formations); arfvedsonite, quartz, fayalite (granites, syenites).
The mineral was named to honor the Swedish chemist, M.A. Ludwig Hedenberg, who first described the species.
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