This International Standard specifies the following four test methods for the determination of the hygroscopic moisture content of test samples: Method 1 - Gravimetric method; Method 2 - Karl Fischer volumetric method; Method 3 - Karl Fischer coulometric method; Method 4 - Mass-loss method. Any of these methods is applicable wherever the analytical value of a chemical constituent is to be calculated to a dried sample basis in the following ore types. Processed ores containing metallic iron (direct reduced iron). Natural or processed ores in which the sulfur content is greater than 0,2 % (mass fraction). Natural or processed ores in which the combined water is greater than 2,5 % (mass fraction). Any of these methods is applicable to a concentration range of 0,05 % (mass fraction) to 4,5 % (mass fraction) hygroscopic moisture. NOTE 1 Where the reportable moisture content of a commercial consignment of ore is required, the procedure in ISO 3087 is used. NOTE 2 With natural or processed ores outside the field of application specified in a), b) or c), a determination of a constituent at any level of concentration may be conducted using any of these methods, or as specified in ISO 7764. NOTE 3 Alternatively, the loss or ignition content may be measured as an estimate of the combined water content.