Sericite mica

Photograph 10-21 Thin section of high-silica shale particles in white-cement raw feed. Grain at left has well-oriented sericite mica flakes grain on right shows very finely microcrystalline assemblage of quartz, clay, and mica. (S A6889)... 

The predominant gangue minerals vary with different types of ore deposits quartz, chalcedonic quartz, adularia, calcite, smectite, interstratified mica/smectite, interstratified chlorite/smectite, sericite, zeolites and kaolinite in Au-Ag rich deposits chlorite, quartz, sericite, carbonates (calcite, rhodoehrosite, siderite), and rare magnetite in Pb-Zn rich deposits chlorite, serieite, siderite, hematite, magnetite and rare epidote in Cu-rich deposits (Sudo, 1954 Nagasawa et al., 1976 Shikazono, 1985b). 

In metamorphic rocks, muscovite occurs in low-grade terrains of the regional metamorphism (albite-chlorite-sericite schists). It must be noted here that the term sericite identifies fine-grained white micas (muscovite, paragonite). 

The volcaniclastic rocks hosting the Boomerang massive sulfide show a wide range of petrographic and chemical compositions. Petrographically the HW volcaniclastic rocks show increasing finegrained white mica (muscovite/sericite) development with proximity to the mineralized horizon. The abundance of these phyllosilicates enhances the development of more intense foliation in... 

Strong bleaching and alteration of host siltstones only occurs proximal (< 2 m) to the veins, whereas spot-bleaching occurs more distally (< ca. 10 m) and is commonly not spatially associated with quartz veining. Alteration in coarsegrained sedimentary rocks is subtle and is accompanied by an increase in sulfides (typically pyrite) along with chlorite+sericite (white mica) and carbonate. 

Probably the most passionately debated mineral (if one might use this adverb in a discussion of clays) found in argillaceous sediments, rivalling perhaps the enigmatic dolomite and dolomitization in the realm of sedimentary rocks, is the mineral or group name illite. Defined and redefined by its originator, R. E. Crim debated and further redefined, denied a proper existence and reprieved, this species has attracted the attention of clay mineralogists for the past two decades. It represents, in fact, the dominantly potassic, dioctahedral, aluminous, mica-like fraction of clay-size materials. Known as sericite or hydro-mica in studies of hydrothermal alterations, soil mica or illite in soils and illite... 

Studies of hydrothermal alteration products associated with ore mineralization in acidic rocks have established the general propensity for the original minerals to be replaced by illite, sericite or hydromica in the innermost zone near the source of hydrothermal fluids and by kaolinite or expandable minerals further from the vein or center of fluid emanation. The newly-formed "mica" can be 2M, 1M, or lMd in polymorph and range compositionally from muscovite to a low potassium, silicic species which can be assimilated in the term illite (Lowell and Guilbert, 1970 Schoen and White, 1966, 1965 Kelly and Kerr, 1957 Bonorino, 1959 Tomita, e al., 1969 Yoder and Eugster, 1955 Meyer and Hemley, 1959, among many authors). 

In zones of hydrothermal alteration it is apparent that the formation of dioctahedral montmorillonites is limited by temperature. They almost never occur in the innermost zone of alteration, typically that of sericitization (hydro-mica or illite), but are the most frequent phase in the argillic-prophylitic zones which succeed one another outward from the zone where the hydrothermal fluid is introduced in the rock. Typically, the fully expandable mineral is preceded by a mixed layered phase (Schoen and White, 1965 Lowell and Guilbert, 1970 Fournier, 1965 Tomita, et al., 1969 Sudo, 1963 Meyer and Hemley, 1959 Bundy and Murray, 1959 Bonorino, 1959). However, temperature is possibly not the only control of expandable clay mineral occurrence, the composition of the solutions and the rock upon which they act might also be important. It is possible that high magnesium concentrations could form chlorite, for example, instead of expandable minerals. 

The term sericite is frequently used to describe fine-grained dioctahedral micas. This material is usually coarser than illites and often hydrothermal in origin. Sericites... 

In addition to conglomerates and quartzites the underlying rocks contain a sequence of two-mica and muscovite (sericite) schists with a small admixture of free carbon (0.2-0.4%). The sericite-biotite phyllitic schists immediately beneath the iron-ore sequence often are carbon-bearing (of carbonaceous schist type). The average carbon content in the underlying schists is 0.45%. 

Major components of the pressed powder blusher include the powder phase and binder (or oil) phase. Components of the powder phase include mineral powder fillers such as talc (a magnesium silicate), mica (a magnesium ahuninum silicate), sericite (a form of hydrated mica), and kaolin (known as China clay). Talc is the most popular of all fillers used, as it tends to be virtually transparent depending on the particle size, and it is very soft to the touch. Although mica is also used extensively as a result of its transparency and smooth texture, it often exhibits a shiny appearance with skin application and has poor compression characteristics when used in a pressed powder. Modern non-oil control formulations rarely contain kaolin, as it tends to exhibit course texture, an extremely matte appearance, and excessive oil-absorption capabilities. Dry binders are also used to allow tlie compressed powder to retain form these include metallic soaps such as zinc stearate and magnesium stearate and... 

There exists a group of minerals that is structurally similar to the micas, but contain less potash and more combined water than the latter. These materials are called illites, but have also been called hydrous micas or sericites. 

CAS 12001-26-2 EINECS/ELINCS 310-127-6 Synonyms Cl 77019 Mica silicate Muscovite mica Phlogopite Sericite Suzorite mica... 

Nikkol Sericite t[Nikko Chems. Co. Ltd http //www.nikkol.co.jp/index.html]-. Oil Well Coarse [Zemex Mica... 

S-100 [U.S. Cosmetics http //WWW. uscosm. com] S-152 [U. S. Cosmetics http //www.uscosm.com]. Satin Mica [Rona Merck KGaA http //www.merck.de, S. Black http //www.sbiack.com]-, Sericite 300S [LCW http //www.icw.fr], Sericite DNN t[lkeda http //www.ikeda-corp.co.jp, S. Black http //WWW. sbiack. com]... 

Nikkoi Seiachyi Aicohoi. See Selachyl alcohol Nikkoi Sericite. See Mica Nikkoi Smectite SWN. See Smectite Nikkoi Sodium Hyaiuronate. See Sodium hyaluronate... 

Sericin, Sericite 300S, Sericite DNN, Sericite FSE, Sericite GMS4C, Sericite S-100, S-152, Sericite SL Sericite SLZ, Sericite SP Sericite. See Mica... 

S-100 S-152 Satin Mica Sericin Sericite 300S Sericite DNN Sericite FSE Sericite GMS 4C Sericite S-100, S-152 Sericite SL Sericite SLZ Sericite SP... 

Other associated terms used in the pigment hterature include muscovite mica, graphitic mica (a dark grey form containing small quantities of graphite) and sericite (a fine-grained muscovite). 

Pyrophyllite (aluminium silicate hydroxide) Sericite (fine grained mica)... 

Heinrich, E. W., and A. A. Levinson, 1955. Studies in the mica group polymorphism among the high-silica sericites. Am. Mineral. 40 983. 

Soil micas exhibit a wide variety of compositional, structural, and morphological features. This is also reflected by the nomenclature used in soil mineralogy. Hydrous mica, micaceous clay, sericite, illite, and degraded illite are some of the terms used, partly synonymously for the general description of fine-grained micas in soils, and partly with special reference to particular deviations from the ideal mica structure. 

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