Precipitate systems display a variety of beautiful patterns. Of particular interest are those patterns formed by more than one insoluble salt. Guided by a prior theoretical model, we present here experiments on two precipitate patterning using PbI₂ and PbF₂ as the precipitating salts, in agar gel medium. Throughout the study, a solution of Pb²⁺ is allowed to diffuse into a homogeneous solution of the two halides and not the reverse. Two major categories of patterns are obtained: periodic, in which the band locations follow a rigorous spacing law, and aperiodic, where the bands occupy erratic spatial positions. The former patterns are obtained at large values of the mean concentration difference Δ [≡(Δ_I + Δ_F)/2, where Δ_I = [Pb²⁺]₀ − 1/2[I⁻]₀ and similarly for Δ_F], while the latter are formed at relatively low values of Δ. The periodic patterns show two different types of behaviour. When Δ_I = Δ_F, one type of bands containing the two precipitates is obtained, obeying the spacing law rigorously. When Δ_I ≠ Δ_F, two types of bands are observed with two distinct spacing laws. A chemical analysis of the bands shows that in both cases, the latter consist of a complete overlap of PbI₂ and PbF— (i.e. no alternation) consistent with the initial ratio of concentrations (of I⁻ to F⁻). Different observations favour the mechanism of post-nucleation patterning. Some special features indicate the role of the kinetics of particle growth in deciding whether we obtain one or two types of bands (and hence one or two spacing laws).