Explanatory notes
… guanine and hypoxanthine and obtained from the scales of certain fish, or (b) a synthetic nacreous (pearl) pigment … deposited by vaporisation, cathodic sputtering, etc., on a supporting sheet of any material (e.g., paper, plastics). … mixtures of colouring matter with other substances (e.g., inert diluents, surface-active products which encourage the …