This part of ISO 787 specifies a general method of test for determining the water-soluble sulfates, chlorides and nitrates of pigments. NOTE When this general method is applicable to a given pigment, a cross-reference to it will simply be included in the International Standard relating to the pigment, with a note of any detailed modification which may be needed in view of the special properties of the pigment in question. Only when this general method is not applicable to a particular pigment will a special method for determination of water-soluble sulfates chlorides or nitrates be specified.