Process of making a compound having a spinel structure

A process of making a compound having a spinel structure comprising:

• (a) introducing into a reactor solid phase reactants comprising an iron-containing metal and at least one constituent capable of forming a metal oxide having a spinel structure;
• (b) introducing pure oxygen into the reactor in a manner to create and maintain in the reactor an oxidizing environment having oxygen present in an amount adequate for forming the compound having a spinel structure;
• (c) generating sufficient heat within the reactor in the presence of the adequate amount of oxygen to heat and melt the reactants at a temperature of about 2700.degree. F. to about 3000.degree. F. to oxidize the reactants and form a molten oxide bath capable, upon cooling, of forming largely the compound having a spinel;
• and
• (d) cooling the oxidized molten reactants in the molten oxide bath to convert iron and at least a portion of the constituent capable of forming a metal oxide having a spinel structure into the compound having a spinel structure, the compound comprising iron and at least the portion of the constituent chemically bound in the spinel structure, the compound having a spinel structure being largely the product formed.