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Mineral definition and classification
To be classified as a "true" mineral, a substance must be a solid and have a crystal structure. It must also be an inorganic, naturally-occurring, homogeneous substance with a defined chemical composition. The chemical composition may vary between end members of a mineral system. For example the plagioclase feldspars comprise a continuous series from sodium-rich albite (NaAlSi3O8) to calcium-rich anorthite (CaAl2Si2O8) with four recognized intermediate compositions between. Mineral-like substances that don't strictly meet the definition are sometimes classified as mineraloids. Other natural-occurring substances are Nonminerals. Industrial minerals is a market term and refers to commercially valuable mined materials (see also Minerals and Rocks section below).
A crystal structure is the orderly geometric spatial arrangement of atoms in the internal structure of a mineral. There are 14 basic crystal lattice arrangements of atoms in three dimensions, and these are referred to as the 14 "Bravais lattices". Each of these lattices can be classified into one of the six crystal systems, and all crystal structures currently recognized fit in one Bravais lattice and one crystal system. This crystal structure is based on regular internal atomic or ionic arrangement that is often expressed in the geometric form that the crystal takes. Even when the mineral grains are too small to see or are irregularly shaped, the underlying crystal structure is always periodic, and can be determined by X-ray diffraction.
Chemistry and crystal structure together define a mineral. In fact, two or more minerals may have the same chemical composition, but differ in crystal structure (these are known as polymorphs). For example, pyrite and marcasite are both iron sulfide, but their arrangement of atoms differs. Similarly, some minerals have different chemical compositions, but the same crystal structure: for example, halite (made from sodium and chlorine), galena (made from lead and sulfur) and periclase (made from magnesium and oxygen) all share the same cubic crystal structure.
More on [ Mineral ]
Mineral Exploration and Extraction :: Mining and Drilling
Soil Mineralogy :: Soils
Geochemistry :: Earth Sciences
Education :: Rocks and Minerals
Gemstone :: Rocks and Minerals
Rockhounding :: Rocks and Minerals
Petrology and Mineralogy :: Journals
Crystallography :: Physics
Hydrothermal venting at pressure-temperature conditions above the critical point of seawater, 5°S on the Mid-Atlantic Ridge
Active deformation across the Sumatran forearc over the December 2004 Mw9.2 rupture
Role of seismogenic processes in fault-rock development: An example from Death Valley, California
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Barahona Micromounts - Pictures of micromount minerals mostly from Spain; features the discovery of the mineral Cobaltarthurite.
French Association of Micromineralogy - Information, images and references related to micro minerals and French mineral localities and a directory of worldwide collectors.
Meta Description: [ Premier site dedie a la micromineralogie et au micromontage avec le cahier des micromonteurs, des annuaires, des photos de mineraux.First site dedicated to the micromineralogy and micromounting with the Cahier des Micromonteurs (quaterly newsletter), some mineral photos, directories, bibliographi... ]
Ken's Fluorescent Minerals - Includes photos of fluorescent minerals, reference sources, and links.
Lithos and Minerals - Image libraries and some information on zeolites (mostly from India) and their associated minerals.
Meta Description: [ Lithos & Mineralien is a rockshop dedicated to quality mineral specimen, especially zeolites. ]
Mineral Cabinet - Photos and descriptions of the mineral collection at the Institut for Mineralogy/Petrography, University of Bremen, Germany.
Meta Description: [ Department Mineralogy/Petrography, mineral cabinet, mineral gallery, mineral collection, mineral pictures ]
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Mineral Identification Project - On-line mineral identification program for 300 of the most common minerals with links to photographs and detailed descriptions.
Minerals and Mineralogy - Descriptions and photography of several common minerals.
Meta Description: [ An introduction into the world of minerals ]
Minerals of Iowa - Pictures and descriptions of minerals of the state from the Iowa Department of Natural Resources - Geological Survey.
Minerals of Scotland - Contains articles on Scotland's minerals, over 235 photographs, 70 location-specific photographs, with pages and photographs about minerals of the United Kingdom.
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Minerals of Utah - Detailed descriptions of mineral collecting sites through out Utah. Content includes geological and mineralogical information as well as localities listed by counties.
MineralTown.com - Educational articles, reports about collecting locales, images, and other resources for collectors of minerals and fossils.
Meta Description: [ Rocks and minerals collecting, Resources for worldwide mineral and fossil collectors with articles, mineral photo gallery, search engine, and free buy,sell or trade collection,fossils and minerals ads. ]
Minrls Mineral Software - Software devoted to the identification, understanding, and collection of minerals.
Meta Description: [ Mineral pictures, identification, descriptions,properties, crystallography, and much more in an easy-to-use program for rockhounds, collectors, mineralogists, geologists, and earth science teachers ]
Steve Condon - A non-commercial web site with fossil and mineral related images.
The Mineral and Gemstone Kingdom - An interactive reference guide to rocks, minerals, and gemstones.
Meta Description: [ An interactive reference guide to rocks, minerals, and gemstones. ]
The Zeolite Homepage of Volker Betz - Information and photography on natural zeolites, references on zeolite locations, and offers for swapping with other collectors.
Timberlake Rose Rock Museum - Located in Noble, Oklahoma. Information and pictures on the local barite mineralization.
Meta Description: [ Timberlake Rose Rock Museum located in Noble, OK just three miles south of the University of Oklahoma. Noble is the world's capital for the barite rose rock. The barite rose rock is the state rock of Oklahoma. ]
| Bare Minerals application. Note that my methods are different than the suggested methods shown on the Bare Minerals DVD ... | |
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