Barite BaSO

For comparison with Tables I and II, Table lit gives the range and typical values of the mineral distributions observed in bituminous coals by the CCSEM and Mossbauer techniques, derived from studies of perhaps a hundred different bituminous coal samples in this laboratory. Some obvious differences in mineralogy are apparent. In addition to the difference in calcium dispersion and abundance already noted, it is seen that certain minerals common in bituminous coals, such as Fe-bearing clays (illite and chlorite) and siderite, are virtually absent in the low-rank samples of Tables I and II. Conversely, minerals such as barite (BaSO ), apatite (Ca5(P0 )30H), and other Ca, Sr phosphates are rather uncommon in bituminous coals. 

Sulfur occurs as the free element—predominantly Sg molecules—and in metal sulfides such as galena, PbS iron pyrite, FeS2 and cinnabar, HgS. To a lesser extent, it occurs as metal sulfates such as barite, BaSO, and gypsum, CaSO - 2H2O, and in volcanic gases as H2S and SO2. 

Besides the precipitation of mineral phases, dissolution of numerous minerals initially supplied to the seafloor can occur in sediments that experience sulfate reduction and/or sulfate-depleted conditions. Iron (oxyhydr)oxides and barite (BaSO ) are two examples with particular relevance for paleoceanographic research. 

A second sedimentary component important for paleoceanographic reconstructions, which is prone to dissolution under conditions of sulfate reduction - or more precisely in srrlfate-depleted sediments - is the barium sulfate mineral, barite (BaSO ). Since a correlation has been detected between barite deposition and the flux of organic matter through the water column, the concentration of barite in sediments has been proposed and applied as a geochemical tracer to reconstruct past changes in ocean productivity (e.g.. Bishop... 

Sulfur is a component of numerous minerals. Sulfides include iron pyrite ( fool s gold, FeS ), zinc blende (ZnS), galena (PbS), and cinnabar (HgS). Sulfates include gypsum (CaSO H O) and barite (BaSO ). These ores are among industry s principal sources of copper, zinc, lead. 

Example 2.9 Solubility product of barite BaSO at 25 °C is equal to 1.08-10 °. It is necessary to determine its solubility in pure water. The barite dissolution reaction is... 

The magic stones also found their way to Gahn and his laboratory in Falun. After Scheele s fundamental work with barium, Gahn could rapidly establish that barium was also the main component in Bolognian Stone. Cascariolo had carried out his experiments with barite BaSO,. 

The most common sulfate compounds are SrSO, BaSO, and PbSO, which are all white solids. Minerals that contain these compounds include celestite (SrSO ), barite (BaSO ), and anglesite (PbSO ). Minerals that contain calcium sulfate (CaSO ) are relatively common, and... 

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