Geochemical aspects of Calcite and Dolomite deposits around Rajawaka off Balangoda, Sri Lanka, and suitability for industry

Abstract

Major calcite and dolomite occurrences are found in Rajawaka off Balangoda in Sri Lanka. The area is undertaken by Precambrian marble rock which is one of the most common sources of calcite and dolomite in Sri Lanka. Field investigation, locating sample points, analytical work using AAS, ETDA titration, colorimetric methods and microscopic analysis were carried out in different phases to obtain chemical and mineralogical composition of calcite and dolomite. Results revealed that the marble samples contain major proportion of calcite mineral, calcitic marble with minor amount of dolomite. Quartz, graphite, pyrite, diopside, apatite, muscovite, phlogopite and biotite occur as accessory minerals. Also, analytical data showed an average acid insoluble of 5.73% and SiO2 of 4.71%, moderately high CaO content` of 81.71%, with low MgO content of 4.91% and very low iron oxide content of 0.37% and aluminum oxide content of 1.62%. These characteristics make this deposit suitable for major industrial uses especially the production of high quality lime and fertilizer manufacturing industries, and it is not suitable for the high-quality glass industry due to high content of silica and other accessories.