| Physical properties of minerals |
We can classify minerals by their physical properties, optical, electrical, magnetic and chemical composition, although the latter is the usual method, and most can be identified by spectroscopic and even visual observation. However, chemical analysis is the only way to accurately identify the nature of a mineral.  The physical properties are of great importance in the study of minerals. Many can be easily seen, or use a spectroscope. Hardness of a mineral The hardness of a mineral is the resistance that has to be scratched. A mineral has a hardness greater than another when the former is able to scratch the second. The German mineralogist Mohs established in 1822, a measuring scale that bears his name, and is used today, in which each mineral can be scratched by those that follow. 10 minerals are taken comparative softer to harder, they are: talc, gypsum, calcite, fluorite, apatite, orthoclase (feldspar), quartz, topaz, corundum and diamond. Tenacity or cohesion The tenacity and cohesion is greater or lesser degree of resistance of a mineral to breakage, deformation, crushing, bending or spraying. We distinguish the following classes of tenacity: - Fragile: is the mineral that breaks down or sprayed with ease. Examples: quartz and sulfur. - Malleable: you can be beaten and spread in sheets or plates. Examples: gold, silver, platinum, copper, tin. - Ductile: which can be reduced to thin threads or wires. Examples: gold, silver and copper. - Flexible: If it bends easily, but again fails to get pressure, it is not able to recover its original shape. Examples: gypsum and talc. - Elastic: that can be bent and, after receiving pressure stops, recovers its original shape. Example: mica.
Only registered users can write comments!
Powered by !JoomlaComment 3.20
3.20 Copyright (C) 2007 Alain Georgette / Copyright (C) 2006 Frantisek Hliva. All rights reserved." |
|||||