- a silicate mineral, chiefly of calcium, magnesium, iron, and aluminum: a dark-green to black variety of monoclinic pyroxene, characteristic of basic rocks.
Origin of augite
1780–90; < Latin augītis a kind of precious stone < Greek, equivalent to aug(ḗ) sunlight + -ītis, feminine of -ītēs -ite1
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Examples from the Web for augite
Pyroxene, quartz and augite form the groundmass, as seen in section.The Long Labrador Trail
Augite, when it occurs, is sometimes green, at other times purple.
These are distinguished from augite by containing little or no aluminium.
Sections of augite crystals from the lavas of 1794 and 1820.Volcanoes: Past and Present
A crystal of augite is shown near the bottom of the drawing.Etna
G. F. Rodwell
- a black or greenish-black mineral of the pyroxene group, found in igneous rocks. Composition: calcium magnesium iron aluminium silicate. General formula: (Ca,Mg,Fe,Al)(Si,Al) 2 O 6 . Crystal structure: monoclinic
C19: from Latin augītēs, from Greek, from augē brightness
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- A glassy, dark-green to black variety of pyroxene. Chemical formula: (Ca,Na)(Mg,Fe,Al)(Si,Al)2O6.
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