EVSC 2800 Lecture Notes - Lecture 5: Huttonite, Chromite, Franklinite
12 May 2016
School
Department
Course
Professor
Document Summary
Crystallization- the growth of a solid from a gas or liquid whose constituent atoms come together in the proper proportions and take on a crystalline arrangement. Freezing as a magma cools below its melting point. The major groups are: silicates (quartz, sio2, carbonates (calcite, caco3, oxides and hydroxides (hematite, fe2o3, sulfides (pyrite, fes2, sulfates (gypsum, caso4 2h2o, halides (halite, nacl) Typically, only about 30 minerals are common in rocks. (called rock-forming minerals) As ions enter into bonds, their sizes determine how they are arranged in a crystalline structure. Large anions occupy most of the space of the atomic structure. One atom of silicon (small) surrounded by four atoms of oxygen (large) produce a structure of a pyramid with 4 sides a tetrahedron. The silica tetrahedron is the basic building block of all silicate minerals. The tetrahedron may bond with cations or it may coordinate with other tetrahedra. Numerous tetrahedral atoms all isolated from each other: example: olivine.
