Briefly summarizes the 80-year history of the use of micaceous iron oxides for the protection of railway civil engineering structures in Britain and elsewhere. Gives scanning electron micrographs, optical photomicrographs, x-ray diffraction patterns, wet analysis results to B53981; and Moessbauer absorption of the pigments, both micaceous and granulas iron oxides from different parts of the world, shows that only the French and Austrian samples are entitled (on account of their laminate structure, high iron oxide content and particle size) to be called micaceous iron oxides. The close similarity of crystalline structures and chemical composition of the English and Austrian pigments explains why both give good protection and suggests that the French pigment will also give good protection.