[pahy-rok-seen, puh-, pahy-rok-seen]
- any of a very common group of minerals of many varieties, silicates of magnesium, iron, calcium, and other elements, occurring as important constituents of many kinds of rocks, especially basic igneous rocks.
Origin of pyroxene
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for pyroxene
There is also a small amount of hematite, pyroxene and sericite.
Pyroxene, quartz and augite form the groundmass, as seen in section.
The lava is black, rich in pyroxene, and strongly attracted by a magnet.
The pyroxene is morphic, yellow or green, and is surrounded by formless areas of nepheline.
Both Great and Little Ararat consist entirely of volcanic rocks, chiefly andesites and pyroxene andesites, with some obsidian.
- any of a group of silicate minerals having the general formula ABSi 2 O 6, where A is usually calcium, sodium, magnesium, or iron, and B is usually magnesium, iron, chromium, manganese, or aluminium. Pyroxenes occur in basic igneous rocks and some metamorphic rocks, and have colours ranging from white to dark green or black. They may be monoclinic (clinopyroxenes) or orthorhombic (orthopyroxenes) in crystal structure. Examples are augite (the most important pyroxene), diopside, enstatite, hypersthene, and jadeite
C19: pyro- + -xene from Greek xenos foreign, because it was mistakenly thought to have originated elsewhere when found in igneous rocks
- Any of a series of dark silicate minerals having the general chemical formula ABSi2O6, where A is either calcium (Ca), sodium (Na), magnesium (Mg), or iron (Fe), and B is either magnesium, iron, chromium (Cr), manganese (Mn), or aluminum (Al). Pyroxenes vary in color from white to dark green or black and are characterized by a rectangular-shaped cross section. They can be either monoclinic or orthorhombic and occur in igneous and metamorphic rocks. The minerals enstatite, diopside, and augite are pyroxenes.
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