This image depicts the structure of pyrope garnet. White spheres are oxygen ions; black are silicon ions; blue are aluminium ions; and red are magnesium ions. — Photo: Kent G. Budge · CC BY-SA 4.0
Pyrope
Also known as: Bohemian garnet.
The magnesium garnet — the only garnet that is always red, its name meaning 'fire-eye'.
Intro adapted from Wikipedia (CC BY-SA).
Pyrope is an IMA-recognized mineral species in the silicate class, with the chemical formula Mg₃Al₂(SiO₄)₃.
It crystallizes in the cubic crystal system (space group Ia-3d). It is a member of the Garnet structural group.
Key properties: Mohs hardness 7–7.5; specific gravity 9.593; typically red or brown or purple or pink; White streak; Vitreous. Optical Class. Isotropic. n = 1.714 luster; refractive index 1.732.
IMA symbol Prp, grandfathered status — known before the IMA’s founding, named in 1803.
Found in ultramafic rocks, as peridotites, kimberlites, eclogites, serpentinites, and in "hornblende" -garnet-plagioclase rocks and anorthosites. Also in amphibole and biotite schists, and as a detrital mineral.
It is found associated with Ilmenite, phlogopite, olivine, "hornblende, " plagioclase, pyroxenes, diamond, kyanite, rutile, chlorite, titanite, glaucophane, omphacite.
Its name comes from the Greek for fire like because of its fire-red color.
Collections: Gemstones, Collector Favorites.