Talc chlorite

Regularly interstratified (1 1) chlorite and vermiculite has been attributed to the mineral corrensite [12173-14-7] (141). Chlorite mixed layers have been documented with talc, vermicuhte, smectite, iUite, biotite, kaolinite, serpentine, and muscovite. The mixed-layer mineral is named after the components, eg, talc—chlorite. The eadier Hterature, however, has reference to specific minerals such as kulkeite [77113-95-2] (talc—chlorite and tosudite... 

One of the major problems associated with beneficiation of PGM from sulphide-dominated deposits is the presence of hydrophobic gangues, such as talc, chlorites, carbonates and aluminosilicates. The concentrates produced in most of the Morensky Reef operations (South Africa) varies from 80 to 150 g/t of combined PGM, where most of the contaminants are silicates, aluminosilicates and talc (i.e. up to 60%). The major hydrophobic gangue depressants used are carboxymethyl cellulose (CMC) and different modifications of guar gums. 

Another common alteration involves the replacement of serpentine by chlorite, resulting in a rock composed solely of chlorite and magnetite. Further replacement by talc or talc-carbonate will result in a talc-chlorite (-carbonate) soapstone. Other alterations can result in the formation of tremolite-talc or chlorite-tremolite-talc soapstones. 

Geologically and genetically, clay minerals are difficult to define simply and adequately, but broadly they are layer lattice silicates of secondary origin. In the same classification are the micas, talc, chlorites, and serpentines which are not strictly clay minerals. In this context, secondary origin means that mineral formation has arisen from the weathering of primary or igneous rock, e.g. granites and basalts. 

Lithicoat P2F, T3F, T4A - grades for matt wood-free art paper which are the mixtures of talc, chlorite and dolomite... 

Iron-poor loganite, pyrosclerite, talc-chlorite... 

A regular chlorite-vermiculite interstratification has been reported by Slat et al. [1959] from an ore-bearing rock of the Vosges, France. This particular mineral gives a 23.9 A reflection on heating. Alietti [1958] has reported interstratifications of saponite-talc, chlorite-saponite, and chlorite-vermiculite in serpentine rocks of Monte Chiaro in Italy and has also (1963) reported a chlorite-montmorillonite interstratification in Alpine and Appennine felspathic rocks. 

Pure talc is thermally stable up to 930°C, and loses its crystalline bound water (4.8%) between 930 and 970°C, leaving an enstatite (dehydrated magnesium siUcate) residue. Most commercial talc products have thermal loss below 930°C on account of the presence of carbonates, which lose carbon dioxide at 600°C, and chlorite, which loses water at 800°C. Talc is an insulator for both heat and electricity. 

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). 

Quartz is abundant in siliceous ore, barite ore and tetsusekiei ore. Minor amounts of Mg-minerals (talc, Mg-chlorite) occur in sekko ore. Chlorite occurs in. sekko ore and it contains high amounts of Mg (Fig. 1.18). 

Mica, kaolins (kaolinite and halloysite), Mg-rich chlorite, talc, montmorillonite and chlorite/montmorillonite are abundant in the host epiclastic sediments and pumiceous tuffs at Jade in the Okinawa Trough (Marumo and Hattori, 1997). 

Hydrothermal alteration minerals from midoceanic basalt are analcite, stilbite, heulandite, natrolite-mesolite-scolecite series, chlorite and smectite for zeolite facies, prehnite, chlorite, calcite and epidote for prehnite-pumpellyite facies, albite, actinolite, chlorite, epidote, quartz, sphene, hornblende, tremolite, talc, magnetite, and nontronite for green schist facies, hornblende, plagioclase, actinolite, leucoxene, quartz, chlorite, apatite, biotite, epidote, magnetite and sphene for amphibolite facies (Humphris and Thompson, 1978). 

Ore Sulphide-dominated PGM ore containing nickel, pyrrhotite and a little copper. Floatable gangue was dominated by talc and chlorites... 

Amplats - Mine 3 South Africa, Morensky Reef Grind To a K%0 of 87 pm Reagents CUSO4 = 100-200 g/t, dibutyl xanthate = 320 g/t. Modified guar gum = 200-250 g/t Metallurgy 90-100 g/t total PGM in concentrate, PGM recovery = 80-82% Ore Sulphide-dominated PGM deposit containing Cu/Ni and mixed pyrite-pyrrhotite. The main floatable gangues are calcite, chlorites with lesser talc... 

In Eq. 19.2, talc represents the magnesimn hydroxide component of various secondary minerals such as chlorite and amphibole.) As a result, sulfete is stripped out of the hydrothermal fluids. 

H20(a) = diaspore, gibbsite, serpentine, dioctahedral micas H20(b) = chlorites, talc, trioctahedral micas, amphiboles... 

The bedrock source of the 10s to 100s of Cr-diopside grains in tiii across the region has not yet been found, in spite of the predominance of pyroxenites and peridotites in the TNB, remnants of primary Cr-diopside are scarce because most rocks have been metamorphicaiiy and metasomaticaiiy aitered such that serpentine has repiaced oiivine and orthopyroxene and amphiboie, chlorite, talc and carbonate has replaced clinopyroxene. Be-cause the Cr-diopside source is unknown, their compositional range and relationship to Ni-mineralization cannot be determined. 

Fig. 2.13 The 1 1 and 2 1 layer arrangements in the sheet structure minerals and the (010) view of the structures of the serpentine, clay, talc, pyrophyllite, mica, and chlorite minerals. X = layer charge per formula unit. [From Bailey (1980), Fig 1.1, p. 3 Fig 1.2, p. 6.1...

The chlorites are a group of sheet silicate minerals similar to the micas and talc. The general formula, A5 6T40io(OH) j, is deceptively simple. The range of possible substitutions is enormous, for example, A = Mg, Al, Fe, ... 

The chlorites are a group of minerals with a layered structure, which in many respects resemble the micas. The monocUnic structure of chlorite is one of regularly alternating talc-Uke Y6Z802o(OH)4 and brucite-like Y6(OH)i2 sheets. 

Figure 1. Representation of the ideal compositions of some major phyllosilicate phases in the MR - 2R - 3R coordinates. M = muscovite, paragonite P - phlogopite Py = pyrophyllite Kaol = kaolinite S serpentine T = talc Chlor = chlorite, 14 8 or aluminous 7 8 polymorphs Ce = celadonite F = feldspar.

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