GEOL 101 Lecture 3: Geo 101 Lecture 3
Document Summary
Mineral species is speci c combination of composition: (chemical formula) + crystal structure (stacking geometry) Sio2= low quartz, high quartz, tridymite, cristobalite, stishovite, coesite. Minerals with common structure are often given a common name not to be confused with species name. Found on earth"s surface in igneous rocks whose parent magma came straight from the mantle: pyroxene: (ca, mg, fe)sio3. Dark green or black due to iron. Occurs in wide range of igneous rocks: amphibole: (na, k, o)(na, ca, mg, fe)2(mg, fe, ti, al)5(sial)8o22(oh, f, cl)2. Found in metamorphic rocks and some igneous rocks: garnet: (mg, fe, ca)3(al )2si3o12. Usually in metamorphic rocks called metabolites that started out as mud. Six different end members and range of colors: mica: k(al, mg, fe)2-3(al, si)4o10(oh)2. Iron poor varieties are light (muscovite: feldspar: (k, na, ca)al(al, si)si2o8. Found in all kinds of rocks, dominate igneous rocks that formed from melting other crystal rocks: quartz: sio2. Main mineral in most sand and sandstone.
