GEOL 1001 Lecture : GEOL Lecture 6
Document Summary
Often occur as constituents in sedimentary rocks. Calcite and dolomite are the two most important carbonate minerals. Determined by observation or performing a simple test. Serveral physical properties are used to identify hand samples of minerals. Well-developed crystal faces do not always form in nature. Growth of many crystals inhibits development of crystal faces. In halite, bonding of na ions to cl ions results in a cubic shape or form. In diamond, bonding of each c atom four other c atoms gives rise to a tetrahedron with the typical shape of diamond. Minerals with the same composition but different crystalline structures. Phase change is when one polymorph changes into another. Appearance of a mineral in reflected light. Other descriptive terms include vitreous, silky, or earthy. Often highly variable due to slight changes in mineral chemistry. Color of a mineral in its powdered form. Resistance of a mineral to abrasion or scratching. All minerals are compared to a standard.
