Laboratory measurements of density, magnetic susceptibility, remanence, resistivity, and induced-polarization response of New Zealand titanomagnetite sands ('ironsands') were made for different volume concentrations C V of titanomagnetite in the range 10 to 100 percent. Both density rho and magnetic susceptibility kappa of these sands increase monotonically with C V ; the observed variation of kappa as a function of C V can be explained by changes of the resultant relative magnetic permeability mu of a binary mixture of magnetic and nonmagnetic grains. The natural remanence of titanomagnetite sands is small (Koenigsberger ratio Q < 0.2). No significant induced-polarization response could be observed even for mixtures of almost pure titanomagnetite. When placed in an electric field, the titanomagnetite sands were found to be nonconductive.