Trichrome IR 513 is a new passivation based on Cr (III) in order to give a thick conversion coating on zinc and zinc alloy deposits. This formulation is especially developed for pure zinc deposits as well as zinc-iron and zinc-cobalt alloy deposits, provided the alloying element is between 0.1 to 0.5%. When used under recommended conditions and in combination with SEALER 615 automotive standards can be achieved.