Low temperature abiogenic synthesis of dolomite

Endowed with the theoretical knowledge of carbonate evaporation and the pre cipitation of CaMg carbonates from aqueous solutions the authors systematic ally researched the low temperature: formation of dolomite-like carbonates. The results obtained at 40 degreesC indicate that the formation of rhomboh edral CaMg carbonates depends on the solid matter/water ratio (solidus inde x Is). The higher the ratio, the mure MgCO3 enters into the carbonate struc ture. The results also confirm a gradual transition of these relationships from calcite, through Mg-calcite, Ca-dolomite and Q-dolomite (Quasi-dolomit e) to Mg-dolomite (Ca44Mg56). The structure of these synthesised carbonates : is disordered, much like their natural counterparts in lagoons, sabkhas, soil:; etc. When studying Ca-dolomite in the laboratory it was found to res tructure into stable dolomite at 100 degreesC and into calcite at 180 degre esC. Synthetized dolomite (Ca50Mg50) does not show superstructural X-ray re flections and hence it was denominated as a Quasi-dolomite (Q-D).