GEOL 101 Lecture Notes - Lecture 3: Chalcopyrite, Siderite, Anhydrite
Document Summary
~ 80-90% of all marine life, 70% on land. Have low densities and crystalize at low temperatures. Often dark in color and have higher densities. Silica and oxygen form together in a complex ion in the shape of a tetrahedron. Most of the earth"s upper crust and upper mantle are composed of fe, mg, na, Ca, k and al combined with si and o2. Common in basalts and in the upper mantle (fe, mg)2sio4. 2 directions of cleavage that meet at right angles. ~ x = mg, fe and y = ca. Chemically similar to pyroxene (expect contains hydroxyl ions (oh-)) Minerals also cleave in 2 directions but not at right angles. ~ x = ca, na, mn, mg, fe. ~ y = mn, fe, mg, al, ti. Series of silicate minerals crystallizing from magma at different stages during cooling. The fe and mg minerals form a discontinuous series and the feldspars form a continuous series.
