Gold rocks

You are given the mass of the "gold" rock, the amoxmt of heat absorbed, and the initial and final temperature. You are asked to find the heat capacity. 

Alaska, Washington, and Nevada. Ores of the Southeast Missouri lead belt and extensive deposits such as in Silesia and Morocco are of the replacement type. These deposits formed when an aqueous solution of the minerals, under the influence of changing temperature and pressure, deposited the sulfides in susceptible sedimentary rock, usually limestone and dolomites. These ore bodies usually contain galena, sphalerite, and pyrite minerals, but seldom contain gold, silver, copper, antimony, or bismuth. 

In the present time our organosilicon adsorbents found the practice application in such as fields such as, for example 1) the method of spectral-chemical determination of gold Clarke quantities in poor ores and rocks has been applied in analytic practice of geological establishments and research institutes 2) at the first time soi ption process was used in hydro-chemical analyze of fresh water. This method has been allowed to analyze of Baikal water 3) for purification metallurgical waters and waste solutions of chemical-metallurgical plants due to toxic elements 4) for creation the filters for extraction of rare elements, for example, uranium 5) for silver utilization from wasted of cinema-photo manufactory. This method has been applied to obtain the silver of high purity. 

A second separation technique is leaching, which uses solubility properties to separate the components of an ore. For example, modem gold production depends on the extraction of tiny particles of gold from gold-bearing rock deposits. After the rock is crushed, it is treated with an aerated aqueous basic solution of sodium cyanide. Molecular oxygen oxidizes the metal, which forms a soluble coordination complex with the cyanide anion ... 

Several sub-classification.s of epithermal preciou.s-metal deposits have been proposed mineralogy, host-rock composition and elemental association (Lindgren, 1928), gold-silver ratios of metal weights (Ferguson, 1929 Nolan, 1933), mineral paragenesis (Nishiwaki et al., 1971), and production ratios of metals (Heald-Wetlaufer et al., 1983). 

S C and 8 0 of carbonates from southern Kyushu (Hokusatsu gold district) have been studied in detail (Matsuhisa et al., 1985 Morishita, 1993). Morishita (1993) found that the S C values of hydrothermal solution in the district during the mineralization stages were low (—ll%c), compared with that of average crustal carbon (—7%o), suggesting that of hydrothermal solution is controlled by organic carbon in widely distributed sedimentay rocks of the Cretaceous Shimanto Supergroup basement. 

Tonnages of gold, silver and the other associated metal, silver/gold ratio, K-Ar ages and host rocks for the Te-type and Se-type epithermal gold deposits (Shikazono et al., 1990)... 

Hg deposits are distributed along the MTL (Median-Tectonic Line) in Southwest Japan and in Northeast Hokkaido (Fig. 1.184). The deposits are vein or disseminated in form. The deposits are hosted by sedimentary and igneous rocks. No K-Ar age data on the deposits are available. However, from the age of host rocks, the age of igneous activities along MTL and the studies on the movement of MTL and K-Ar ages of Au-veins associated with Hg mineralization in Northeast Hokkaido (e.g., Khonomai), it is likely that these deposits formed at middle Miocene age. However, mercury mineralization in Kitami Province (north Hokkaido) occurred at approximately the same age as the epithermal gold-silver mineralization in the same district (4.5-5.3 Ma) (Maeda, 1997). 

The veins are composed mostly of quartz and a small amount of sulfide minerals (pyrite, pyrrhotite, arsenopyrite, chalcopyrite, sphalerite, and galena), carbonate minerals (calcite, dolomite) and gold, and include breccias of the host rocks with carbonaceous matters. Layering by carbonaceous matters has been occasionally observed in the veins. Banding structure, wall rock alteration and an evidence of boiling of fluids that are commonly observed in epithermal veins have not been usually found. 

In the Yamizo Mountains, the correlation between A Ag and a kind of the host rocks is found A Ag of gold from gold-quartz veins in shale is lower than that in sand.stone. 

Factors in controlling chemical compositions of gold in equilibrium with the ore fluids are temperature, pH, concentration of aqueous H2S and Cl in the ore fluids, concentration ratio of Au and Ag species in the ore fluids, activity coefficient of Au and Ag components in gold, and so on (Shikazono, 1981). In the Yamizo Mountains, as a result, Ag/Au ratios of gold are correlated with a kind of the host rocks and sulfur isotopic compositions of the deposits. This correlation could be used to interpret Ag/Au ratios of gold. 

It is concluded that, in either case, in situ interaction of the ore fluids with the host rocks controls the chemical compositions of gold in the Yamizo Mountains. 

Hot spring-type gold deposits (Nansatsu-type by Urashima et al. (1981,1987), high sulfidation-type by Hedenquist (1987), epithermal Au disseminated-type) are distributed in the Nansatsu district of southern Kyushu (Fig. 1.193). The deposits (Kasuga, Akeshi, Iwato) were formed at Pliocene age (5.5-3.7 m.y.) in the calc-alkaline volcanic rocks of nearly same age (Togashi and Shibata, 1984). The deposits, which are similar to Nansatsu-type deposits, occur in Southwest Hokkaido (Date, Hakurhu). 

Aoki, M. (1988) Gold mineralization in the Osorezan hydrothermal system — Rock alteration and hot spring precipitates. Mining Geology, 38, 64 (in Japanese). 

Ibaraki, K. and Suzuki, R, (1990) Wall rock alteration in the Hishikari gold mine, Kagoshima Prefecture, Japan. Mining Geology, 40, 97-106 (in Japanese with English abst.). 

Naito, K., Matsuhisa, Y., Izawa, E. and Takaoka, H. (1993) Oxygen isotopic zonation of hydrothermally altered rocks in the Hishikari gold deposit, southern Kyushu, Japan. Resource Geology Special Issue, 14, 71-84. 

Shikazono, N. (1985a) Mineralogical and fluid inclusion features of rock alterations in the Seigoshi gold-silver mining district, western part of Izu Peninsula, Japan. Ghent. Geol, 213-230. 

Togashi, Y. and Shibata, K. (1984) K-Ar age for alumite-bearing rock from the Iwato gold deposit, Kagoshima Prefecture, southern Japan. Mining Geology, 34, 281-286 (in Japanese). 

Main opaque minerals are chalcopyrite, pyrite, pyrrhotite, sphalerite and bornite (Table 2.22). These minerals commonly occur in massive, banded and disseminated ores and are usually metamorphosed. Hematite occurs in red chert which is composed of fine grained hematite and aluminosilicates (chlorite, stilpnomelane, amphibole, quartz) and carbonates. The massive sulfide ore bodies are overlain by a thin layer of red ferruginous rock in the Okuki (Watanabe et al., 1970). Minor opaque minerals are cobalt minerals (cobaltite, cobalt pentlandite, cobalt mackinawite, carrollite), tetrahedrite-tennantite, native gold, native silver, chalcocite, acanthite, hessite, silver-rich electrum, cubanite, valleriite , and mawsonite or stannoidite (Table 2.22). 

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