Topics CoveredIntroduction to AugiteProperties of AugiteHow to Identify AugiteGlobal DistributionOccurrence of Augite and Useful Mineral AssociationReferencesIntroduction to AugiteChemical Formula – (Ca,Na)(Mg,Fe,Al,Ti)(Si,Al)2O6Augite is a single chain inosilicate mineral and member of pyroxene group. It was named after the Greek word for luster, manganese mining quarry machine based on the appearance of its cleavage surface.Properties of AugiteThe following are the key properties of Augite:Cell DataSpace Group: C2/ca = 9.699b = 8.844c = 5.272β = 106.97°Z = 4Crystal DataMonoclinicPoint Group: 2/mStubby prismatic crystals, square or octagonal in section, to 10 cm; elongated || [001], acicular, skeletal, dendritic. Exsolution lamellae and overgrowths common. Twinning: Simple or multiple on 100, common; also on 001X-ray Powder Pattern: 2.994 (100), 3.324 (75), 2.949 (65), 2.516 (65), 2.566 (55), 2.134 (35), 2.895 (34)Chemical CompositionElementsContent 1Content 2SiO251.8345.30CaO19.2122.24MgO1611.20FeO7.215.15Al2O33.076.72Fe2O31.383.98TiO20.494.33H2O-0.470.15Na2O0.270.78MnO0.170.19H2O+0.110.05K2O0.020.18Total100.23100.27Optical PropertiesOptical Class: Biaxial (+)Pleochroism: X = pale green, pale brown, green, greenish yellow; Y = pale brown, pale yellow-green, violet; Z = pale green, grayish green, violetOrientation: Y = b; Z ^ c = -35° to -50°; X ^ a = -20° to -35°Dispersion: r > v; weak to moderateAbsorption: Weak; Y > Z > X.α = 1.671-1.735β = 1.672-1.741γ = 1.703{-String.Split-|-1.7742V(meas.) = 25°-61°Estimated PropertiesElectron densityBulk density (electron density)=3.37 g/cm3note: Specific gravity of Augite =3.40 g/cm3PhotoelectricPEAugite = 4.80 barns/electronU= PEAugite x ρElectron density= 16.17 barns/cm3Fermion indexFermion index = 0.02Boson index = 0.98RadioactivityAugite is not radioactiveHow to Identify AugiteAugite occurs in range of colors lead ore crusher from black to dark brown, light brown, green and brown green. It has translucent to opaque appearance with prominent cleavages, vitreous luster and greenish gray streak. It is non-fluorescent and forms massive fibers, granules or columns. Its fractures are brittle producing small, conchoidal fragments. The hardness of augite ranges from 5 to 6.5, and its average density is 3.4 g/cm3.Global DistributionAugite is distributed in the following places:Arendal, NorwayVesuvius, Campania, ItalyFrascati, Alban Hills, LazioMt. Monzoni, Val di Fassa, Trentino-Alto AdigeTraversella, PiedmontMt. Etna, SicilyLaacher See, Eifel district, GermanyUsti nad Labem, Bilina, Czech RepublicAzores and Cape Verde IslandsRenfrew and Haliburton Cos., OntarioOtter Lake, Pontiac Co.,QuebecFranklin and Sterling Hill, OgdensburgSussex Co., New JerseyDiana, Lewis Co., and Fine, St. Lawrence Co., New YorkTomik, kaolin washing machine Gilgit district, PakistanKangan, Andhra Pradesh, IndiaOccurrence of Augite and Useful Mineral AssociationAugite occurs in gabbro, basalt, mafic igneous rocks, metamorphosed iron formations, ultramafic rocks and some high-grade metamorphic rocks. It is closely associated with minerals like pyroxenes, amphiboles, leucite, olivine, labradorite, sanidine and orthoclase.ReferencesAugite – MindatAugite Mineral Data – WebmineralAugite.pdf - Rruff Project Website - University of Arizona Date Added: Feb 2, 2013 | Updated: Jun 11, 2013