Specifies methods of determining the sulphate and pyritic sulphur contents and of calculating the amount of organic sulphur present. The sulphate is determined by extraction coal with dilute hydrochloric acid and determining the sulphate in the extract either gravimetrically or titrimatrically. The pyritic sulphur is determined either indirectly by the amount of iron combined in the pyritic state or by reduction of the sulphur with nascent hydrogen and subsequent iodometrical determination. The organic sulphur is calculated from the difference between the two sulphur forms mentioned above and the total sulphur.