A method of forming a magnetic material. The magnetic material is a solid mass of grains, and has magnetic parameters characterized by: (1) a maximum magnetic energy product, (BH).sub.max, greater than 15 megagaussoersteds; and (2) a remanence greater than 9 kilogauss. The magnetic material is prepared by a two step solidification, heat treatment process. The solidification process is carried out by growing microwave powder or snow. The microwave powder or snow is grown by introducing a reaction gas comprised of precursor compounds of the magnetic material into a substantially enclosed reaction vessel. The reaction gas is energized by providing a source of microwave energy coupled to the substantially enclosed reaction vessel while maintaining the reaction gas pressure high enough to form the powdery microwave polymerizate, condensate, or precipitate, i.e., microwave snow. The solid particles of microwave snow have a morphology characterized as being one or more of (i) amorphous; (ii) microcrystalline; or (iii) polycrystalline. The grains within the solid have, at this stage of the process, an average grain characteristic dimension less than that of the heat treated magnetic material. In the second, or heat treating, stage of the process, the atomized solid particles are heat treated to form a solid material comprised of grains meeting at grain boundaries. The grains and grain boundaries have the morphology of the magnetic material.