Antiferromagnetic particles can exhibit the phenomenon of superparamagnetism if the number of spins on the two sublattices is unequal. Monte Carlo simulations have been performed on spherical Ising particles. The magnetization and small-angle neutron scattering were calculated as a function of temperature. The magnetization as a function of field lies on a universal curve when the field is scaled by the ratio of number of spins in the particle to the number of uncompensated spins. This applies over a wide temperature range. The small-angle scattering is identical to that from a hollow magnetic shell. This suggests a sensitive method of probing the surface magnetization of such particles.