CALCITE IN COAL FROM THE QUINSAM MINE, BRITI!iH COLUMBIA, CANADA; ITS ORIGIN, DISTRIBUTION AND EFFECTS

calcite and possibly other carbonates which coat he surfaces of cleats. If the calcite is not removed by washing then it adds CaO lo that already in the ash. If the ash concentration is low then this addition of CaO can cause the concentration in the ash to rise markedly. The mineralogy of the ash ensures that it also contains some CaO. The concentration of this component of the CaO probably lemains fairly constant from sample to sample and will not vary as thc ash content changes. It therefore cannot be reduced by washing. The component of CaO originating from calcite can be removed from the coal if the calcite is liberated during washing. If it is not removed, the CaO concentration of the ash of thc washed coal may be high and variable.