Abstract: The invention encompasses an ultrafine NFS powder wherein the particle size is sufficiently small as to increase the proportion of the reactive glassy silicate phase in the NFS, methods of making the ultrafine NFS powder, and cementitious products which use the ultrafine NFS powder. The invention also encompasses pozzolanic binders produced by fine grinding non-ferrous smelter slags, as well as methods for processing the non-ferrous slags wherein various chemical additives, such as pH increasing additives, are added to the binders to increase the strength of compositions for uses such as mine backfill or grout mixtures.