ISO 4620:1986

Specifies three types of pigment consisting predominantly of cadmium sulfide or of mixed crystals of cadmium sulfide and cadmium selenide; the cadmium may be partially replaced by zinc. Type 1, concentrated pigments, contain not more than 30 % (m/m) of extenders: type 2, extended pigments, contain not more than 70 % (m/m) of extenders: type 3, these are essentially pure and do not contain any extenders and are mainly suitable for use in ceramics.