Event Title
Location
Parker-Reed, SSWAC
Start Date
1-5-2014 1:00 PM
End Date
1-5-2014 2:00 PM
Project Type
Poster
Description
Augite is typically known for its greenish black color, nice vitreous luster, two directions of cleavage and of course its simple chemical formula: (Ca,Na,Mg,Fe2+,Fe3+Al,Ti)2[(Si,Al)2]O6]. Augite has a hardness of 5.5, 2 planes of cleavage and massive habit. Augite is an important rock-forming silicate mineral and occurs in a wide variety of basic igneous rocks, including gabbros, dolerites and basalts. Augite also occurs in ultrabasic and intermediate rocks as well as a limited number of high-grade metamorphic rocks such as granulites and charnockites. Augites range widely in composition and show a continuoius variation in chemical composition. Iron rich augites are restricted to occurring in ferrogabbros, iron-rich dolerites, syenites, acid volcanic glasses and metamorphosed iron formations. Augites optical properties are as follows. Augite has first and second order interference colors, weak pleocrhoism and an extinction angle at 45. Simple twinning and two planes of cleavage at 90 to each other are present in Aguite in thin section. Augite is a biaxial monoclinic mineral with positive optic sign.
Faculty Sponsor
Tasha Dunn
Sponsoring Department
Colby College. Geology Dept.
CLAS Field of Study
Natural Sciences
Event Website
http://www.colby.edu/clas
ID
351
Included in
My Pet Mineral: Augite
Parker-Reed, SSWAC
Augite is typically known for its greenish black color, nice vitreous luster, two directions of cleavage and of course its simple chemical formula: (Ca,Na,Mg,Fe2+,Fe3+Al,Ti)2[(Si,Al)2]O6]. Augite has a hardness of 5.5, 2 planes of cleavage and massive habit. Augite is an important rock-forming silicate mineral and occurs in a wide variety of basic igneous rocks, including gabbros, dolerites and basalts. Augite also occurs in ultrabasic and intermediate rocks as well as a limited number of high-grade metamorphic rocks such as granulites and charnockites. Augites range widely in composition and show a continuoius variation in chemical composition. Iron rich augites are restricted to occurring in ferrogabbros, iron-rich dolerites, syenites, acid volcanic glasses and metamorphosed iron formations. Augites optical properties are as follows. Augite has first and second order interference colors, weak pleocrhoism and an extinction angle at 45. Simple twinning and two planes of cleavage at 90 to each other are present in Aguite in thin section. Augite is a biaxial monoclinic mineral with positive optic sign.
https://digitalcommons.colby.edu/clas/2014/program/187