King-Maries-Crossley formula

On the other hand, the King-Maries-Crossley formula is a little more complex and attempts to take into account all of the chemical possibilities that can arise when minerals are present ... 

Because of the changes that occur in mineral matter during the ashing procedure, a number of formulas have been devised to allow calculation of the mineral matter content from various parameters determined during analyses of the coal. Minimally, this involves a calculation based on total content of ash and sulfur. The two formulas most commonly used are the Parr formula and the King-Maries-Crossley formula. 

The King-Maries-Crossley formula is a more elaborate formula that allows for a number of effects. The original formula is... 

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