Minerals chemical composition

Tantalum metal dust, exposure to, 24 334 Tantalum minerals, chemical compositions of, 24 315t. See also Tantalum ores Tantalum-Niobium International Study Center (TIC), 24 331 Tantalum nitrides, 24 335 Tantalum ores, 24 316. See also Tantalum minerals... 

In most cases of interest, however, the system represented by equation (5.3.3) is overdetermined and we must enforce the closure condition with a different method. Let us return to a standard mass-balance least-square problem, such as, for instance, calculating the mineral abundances from the whole-rock and mineral chemical compositions. If xu x2,.. -,x are the mineral fractions, which may be lumped together in a vector x, the closure condition... 

Mohs HARDNESS SCALE Mineral Chemical Composition Hardness... 

Mineral. Chemical composition. Colour. Density Hardness (Mohs scale). Crystallo- graphic system. 

Class Mineral Chemical composition Molecular mass, g-mole Solubility ... 

The two end members of this group with mainly tetrahedral substitutions are beidellite and saponite, which are di- and trioctahedral smectites, respectively. The corresponding end members with mainly octahedral substitutions are mont-morillonite and hectorite. Another common smectite, nontronite, is an iron-rich mineral. Chemical compositions of various smectite samples are provided in Table 2. Montmorillonite is the most common mineral of this group it is named for its location in Montmorillon, France. Figures 3d and 3e provide SEM views of the textural morphology of two montmorillonites. A common industrial mineral is bentonite, which is actually a montmorillonite of volcanic ash origin that contains a significant amount of impurities, such as cristobalite (a-quartz), that is intimately mixed with the clay. 

Clark, A. 1993. Hey s Mineral Index Mineral Species, Varieties and Synonyms, 3rd ed. London/New York Chapman Hall. An alphabetical listing of all known minerals, their chemical composition, and type of locality. Also includes an additional finding index arranged by mineral chemical composition. 

Mineral Chemical Composition Mohs Hardness Absolute Hardness... 

Schindler M, Hawthorne FC (2004) A bond-valence approach to the uranyl-oxide hydroxy-hydrate minerals chemical composition and occurrence. Can Mineral 42 1601-1627... 

Mineral and Chemical Composition. X-ray diffraction is used to determine the mineral composition of an Mg(OH)2 sample. Induced coupled plasma (icp) spectrophotometry is used to measure the atomic concentrations present in a sample. X-ray fluorescence analysis is another comparative instmmental method of determining chemical composition. 

None of the natural sulfides of manganese are of any commercial importance. Some siUcates have been mined. Rhodonite and braunite are of iaterest because these are frequendy associated with the oxide and carbonate minerals. The chemical composition of some common manganese minerals are given ia Table 3. 

Flow Sheets. AH minerals processing operations function on the basis of a flow sheet depicting the flow of soHds and Hquids in the entire plant (6,13,14). The complexity of a flow sheet depends on the nature of the ore treated and the specifications for the final product. The basic operations in a flow sheet are size reduction (qv) (comminution) and/or size separation (see Separation, size), minerals separation, soHd—Hquid separation, and materials handling. The overaH flow sheet depends on whether the specification for the final mineral product is size, chemical composition, ie, grade, or both. Products from a quarry, for example, may have a size specification only, whereas metal concentrates have a grade specification. 

With few exceptions, extender pigments can be classified as commodity chemicals. They are manufactured in large quantities with less sophisticated production methods than most pigments. Whereas the majority of pigments is prepared synthetically, extender pigments are mainly manufactured by the beneficiation of natural minerals. Based on chemical composition, extender pigments are carbonate, sulfate, siUca-based, and siUcate-based compounds. 

Talc [14807-96-6], a naturally occurring mineral of the general chemical composition Mg2Si40 Q(0H)2, is a crystalline hydrous magnesium siUc ate belonging to the general mineral family of the layered siUcates. Other layered siUcates are kaolin, mica, and pyrophyUite (1). 

Clays (qv) are aluminosihcate minerals, some of which have definite chemical compositions. In regard to tar sands, however, clay is only a size classification and is usually deterrnined by a sedimentation method. According to the previous definition of fines, the fines fraction equals the sum of the silt and clay fractions. The clay fraction over a wide range of fines contents is a relatively constant 30% of the fines. 

Chry sotile is a hydrated magnesium siHcate and its stoicliiometric chemical composition may be given as AIg2Si20 (0H)4 [12001 -29-5]. However, the geothermal processes wliich ield the chry sotile fiber formations usually involve the co-deposition of v arious other minerals. Tliese mineral contaminants comprise brucite [1317-43-7] (AIg(OH)2), magnetite [1309-38-2] (Fe O, calcite [13397-26-7] (CaCO ), dolomite [16389-88-1] (AIg,CaC02),... 

The complexity of amphibole geology and stmcture is readily understood from their chemical composition. The average chemical composition of amphibole minerals may be represented as (2) ... 

Cathode Reaction. There are many different types of manganese dioxide (18), having varying activity in batteries. The only type suitable for alkaline batteries is y-Mn02, the mineral form of which is nsutite. The chemical composition of has been described (19) by the general formula... 

The choice of selected raw materials is very wide, but they must provide calcium oxide (lime), iron oxide [1309-37-1/, siHca, and aluminum oxide (alumina). Examples of the calcereous (calcium oxide) sources are calcium carbonate minerals (aragonite [14791-73-2] calcite [13397-26-7] limestone [1317-65-3] or mad), seasheUs, or shale. Examples of argillaceous (siHca and alumina) sources are clays, fly ash, mad, shale, and sand. The iron oxide commonly comes from iron ore, clays, or mill scale. Some raw matedals supply more than one ingredient, and the mixture of raw matedals is a function of their chemical composition, as deterrnined by cost and availabiHty. 

The chemical composition of vermiculite can be quite variable (145). The megascopic varieties are generally trioctahedral, and the clay-si2e varieties contain both dioctahedral and trioctahedral varieties (144). Smectite minerals do not commonly occur as macroscopic single crystals. 

Chlorite is another mineral that is commonly associated with mixed-layered clays. Complete soHd solutions of chlorite mixed-layer minerals have not been identified. In contrast to iUite—smectite mixed-layer minerals, chlorite mixed-layer minerals occur either as nearly equal proportions of end-member minerals (Rl) or dominated by one end member (RO) (142). Mixed-layer chlorite may consist of any of the di—tri combinations of chlorite and chlorite mixed-layering occurs with serpentine, kaolinite, talc, vermicuhte, smectite, and mica. References of specific chlorite mixed-layer minerals of varied chemical compositions are available (142,156). 

---