Abstract: A method of making a building block from clay-containing compounds, which includes employing a major amount of such clay-containing material in combination with a calciferous additive and water to cure the shape the same under the influence of controlled pressure and temperature for a pre-determined time to create building block which is characterized by a mineralogical crystalline phase. The clay-containing compound includes a mixture of fine particulate material and coarser particulate material. The product produced by the method is also disclosed.

Abstract: A process of producing magnetite with a high purity of greater than 90% magnetite, more typically greater than 98% magnetite, by reducing powdered hematite into magnetite under maximum temperatures of about 700 to 1300° C. against a counter-current of or concurrent with methane or natural gas in a heating device. The amount of methane used to reduce the hematite may be about 0.18 and 1.8 standard cubic feet of methane per pound of hematite. A product of high purity methane produced from the process is also provided, where the magnetite is below 1 ?M in diameter and has a magnetic saturation greater than 90.0 emu/g. Corresponding apparatus using an improved feeder system for powdered hematite is provided.