Pyroxene

A sample of pyroxenite, a rock consisting mostly of pyroxene minerals.

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 crystals with the general formula XY(Si,Al)₂O₆ where X and Y represents metal ions. Although aluminium substitutes extensively for silicon in silicates such as feldspars and amphiboles, the substitution occurs only to a limited extent in most pyroxenes.

Pyroxenite is an igneous rock made up of minerals from the pyroxene group.

Pyroxene Media

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  First X-ray diffraction view of Martian soil – CheMin analysis reveals feldspar, pyroxenes, olivine and more (Curiosity rover at "Rocknest")

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  A thin section of green pyroxene

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  Mantle-peridotite xenolith from San Carlos Indian Reservation, Gila Co., Arizona, USA. The xenolith is dominated by green peridot olivine, together with black orthopyroxene and spinel crystals, and rare grass-green diopside grains. The fine-grained gray rock in this image is the host basalt.(unknown scale).

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  A single chain of silicon tetrahedra viewed in the [100] direction

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  A single chain of silica tetrahedra viewed in the [010] direction

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  Structure of pyroxene looking along the silica chains. "I-beams" are outlined in green. Silicon ions are oversized to emphasize the silicon chains.