Aerosol routes have been successfully used to produce high temperature superconducting ceramic powders and magnetic oxides. An aqueous solution of the precursor nitrates is atomized, diffusion dried and then thermally decomposed in a tubular reactor. These powders have then been characterized by magnetic susceptibility measurements, X-ray diffraction, element microprobe analysis, thermogravimetry, and Mossbauer spectroscopy. It has been determined that the quench rate at the exit of the reactor has a significant effect on the final powder characteristics for the superconducting powders. The system has also been used to produce magnetic ferric oxide powders with the aim of preferentially producing the γ phase oxide.