Abstract: A method of analysing coal or coke wherein the concentration of ash or mineral matter in coal or coke is determined from (i) the result of a measurement of transmission or scatter of X-rays or .gamma.-rays of a first energy chosen such that there is significant difference in absorption of radiation per unit weight in coal matter and mineral matter excluding iron, combined with (ii) the result of at least one further measurement of transmission or scatter of X-rays or .gamma.-rays at different energy/energies so chosen that there is significant difference in absorption of radiation per unit weight of coal matter and mineral matter and that the relative absorption per unit weights by said coal matter and said mineral matter at any one energy is significantly different from the relative absorption at each other energy including said first energy, and/or (iii) the result of a measurement of iron concentration by neutron capture .gamma.-ray techniques.