Colour of Option may well differ from colorless to quite somewhat yellowish and should darken on prolonged exposure to mild. This darkening does not affect potency. Don't use if precipitate seems.k.?Naphthylindolecarboxylates and Naphthylindazolecarboxylates.—Any compound that contains a naphthylindole carboxylate or naphthylindazole carboxylate