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Aragonite, CaCOs

Aragonite. Calcium carbonate is a common deposit in shallow tropical waters as a constituent of muds, or in the upper part of coral reefs where it precipitates from carbon dioxide-rich waters supersaturated with carbonate from intense biological photosynthesis and solar heating. Deposits of ooHtic aragonite, CaCO, extending over 250,000 km in water less than 5 m deep ate mined for industrial purposes in the Bahamas for export to the United States (19). [Pg.285]

Strontium Carbonate. Strontium carbonate, SrCO, occurs naturally as strontianite in orthorhombic crystals and as isomorphs with aragonite, CaCO, and witherite, BaCO. There are deposits in the United States in Schoharie County, New York in WestphaUa, Germany and smaller deposits in many other areas. None is economically workable. Strontianite has a specific gravity of 3.7, a Mohs hardness of 3.5, and it is colorless, gray, or reddish in color. [Pg.474]

Aragonite CaCOs PBF 11 184 trimorphs calcite, vaterite Bismutite Bi2(C03)02 PBF 11 259... [Pg.166]

Carbonates Aragonite CaCOs, calcite CaCOs, cerussite PbCOs, magnesite MgCOs, strontianite SrCOs, witherite BaCOs... [Pg.7]

CaCOs -7 to 25 CaC03 (calcite) CaCO ., (aragonite) CaCO ., (vaterite) CaC03-6H20 (ikaite) Marion 2001 He and Morse 1993 Plummer and Busenberg 1982... [Pg.32]

Calcite and aragonite = CaCOs (shells of coccoliths and foraminifera, corals)... [Pg.59]

Cerussite (PbCOs) is also naturally abundant and crystallizes in an orthorhombic form isomorphous with strontianite (SrCOs) and aragonite (CaCOs). PbCOs is often found with galena in ore veins because it forms when carbonate-rich waters interact with PbS in the common lead-zinc-limestone ore association (47). The derivative PbCOs Pb(OH)2, known as cemse or white lead , was the most important artificial white pigment in antiquity (3). Ceruse is made by treating naturally occurring lead compounds [mixtures of PbCOs, PbO, and... [Pg.79]

The kinetics and mechanism of the transfonnation of aragonite, CaCOs, (containing 0.025 % Na) into caldte have been investigated using d.t.a., X-my diffraction, and i.r. spectrophotometry. The transformation temperature (476 C) and the energetics of the transformation (AH = 85 kcal mol and = 98 kcal mol ), as determined from the differential thermal curves, are in approximate agreement with previously reported values. A complementary... [Pg.277]

An increase in carbonate-ion concentration moves the equilibrium in favour of calcium carbonate deposition. Thus one secondary effect of cathodic protection in seawater is the production of OH, which favours the production of CO, which in turn promotes the deposition of CaC03-Cathodically protected surfaces in seawater will often develop an aragonite (CaCO ) him. This him is commonly referred to as a calcareous deposit. [Pg.158]

PbCOs as cerusite is orthorhombic and is isomorphous with aragonite CaCOs, stron-tianite SrC03 and witherite BaC03. PbCOs has a density 6-58 g/cc and a unit cell a = 5195 A,6 = 8-436 A and c = 6-152 Al64... [Pg.132]

See other pages where Aragonite, CaCOs is mentioned: [Pg.304]    [Pg.55]    [Pg.58]    [Pg.648]    [Pg.52]    [Pg.3036]    [Pg.2511]    [Pg.838]    [Pg.24]    [Pg.141]    [Pg.40]    [Pg.361]    [Pg.180]    [Pg.30]    [Pg.54]    [Pg.2003]    [Pg.1949]    [Pg.2170]    [Pg.59]    [Pg.11]    [Pg.218]    [Pg.2151]    [Pg.35]    [Pg.296]    [Pg.60]    [Pg.1827]    [Pg.750]    [Pg.2313]    [Pg.2396]    [Pg.1947]    [Pg.452]   
See also in sourсe #XX -- [ Pg.74 , Pg.75 ]



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Aragonite

Aragonite CaCO

Aragonite CaCO

Caco

Calcite and Aragonite CaCO

Calcite, Island Spar and Aragonite CaCO

Minerals aragonite, CaCO

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