The vanadium distribution over equilibrium gas oil and resid resistant cracking catalysts and vanadium-loaded cracking catalysts mixed with calcium-exchanged clay has been determined. The results of secondary ion mass spectroscopy imaging are consistent with cracking activity data and shown vanadium preferentially accumulated on the calcium-exchanged clay in the presence of fluid catalytic cracking catalyst. This indicates that calcium-exchanged clay should be active for vanadium passivation in catalytic cracking.