Dolomites experimental observations

Land (e.g., 198S) has stressed the chemical and structural variations associated with natural dolomites, and has gone so far as to suggest that the name "dolomite" be used in the same way that the mineral name "feldspar" is used. The fact that dolomite is relatively unreactive compared to most other sedimentary carbonate minerals has severely limited experimental studies under temperature and pressure conditions that exist during shallow burial. Consequently, most information on the chemical behavior of dolomite must be obtained from observations of complex natural systems. Such observations are all too often open to multiple interpretations. 

Seawater in the upper regions of the ocean is strongly supersaturated with respect to calcite, aragonite, and ideal dolomite. Why these minerals fail to precipitate directly from it has been a problem of major interest. In experimental studies (e.g., Pytkowicz, 1965, 1973 Berner, 1975), the magnesium ion has been observed to be a strong inhibitor of calcite precipitation and largely responsible for its failure to precipitate... 

Single Mineral Flotation Tests. Experiments conducted in the natural pH range (pH 6.7) as shown in Table I, yielded 88% flotation recovery of apatite at a dodecylamine concentration of 1.6 X 10" kmol/m . Apatite recovery in the absence of NaCI was observed to be 49%. In contrast, dolomite recovery under similar experimental conditions with and without NaCI remained at the 18-19% level. 

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