Abstract: An apparatus for the production of calcium silicate based stone blanks including at least one mold into which a crude mixture is poured, the mixture comprising granulated silicate-containing material, lime, water, a cement and foam. The mold has a cover, a bottom and side plate, with one of the plates being movable to open and close the mold. The crude mixture is heated in the mold essentially uniformly to a temperature between 45.degree. C. and 90.degree. C. until achieving the desired blank-strength by strength-forming reactions of the cement in the crude mixture. The heater used for this purpose is a high frequency voltage heater using two parts of the mold as condensor plates connectable with a high frequency voltage source. The formed stone blanks are thereafter removed from the mold and transferred to a transport station.

Abstract: A process and apparatus is provided for the production of calcium silicate-containing stone blanks which are useful in constructing building walls. A crude mixture, of a granulated silicate-containing material, lime, water, a cement and a foaming agent, is subjected to no more than a minimum application of external pressure and is subsequently hardened in an autoclave. The cement produces the necessary strength for the blank, so that the latter becomes transportable while the final strength is achieved by reaction of the silicate-containing material during the autoclave treatment. In order to arrive at acceptable molding times and in order to achieve a simplified process with slight fragment bulk density and optimal head damping characteristics, the crude mixture is rendered pourable, is filled into molds in a quantity corresponding to the fragment volume of the stone blank, and the crude mixture in the mold is heated essentially uniformly to a temperature between 45.degree. C. and 90.degree. C.

Abstract: A process and apparatus is provided for the production of calcium silicate-containing stone blanks which are useful in constructing building walls. A crude mixture, of a granulated silicate-containing material, lime, water, a cement and a foaming agent, is subjected to no more than a minimum application of external pressure and is subsequently hardened in an autoclave. The cement produces the necessary strength for the blank, so that the latter becomes transportable while the final strength is achieved by reaction of the silicate-containing material during the autoclave treatment. In order to arrive at acceptable molding times and in order to achieve a simplified process with slight fragment bulk density and optimal head damping characteristics, the crude mixture is rendered pourable, is filled into molds in a quantity corresponding to the fragment volume of the stone blank, and the crude mixture in the mold is heated essentially uniformly to a temperature between 45.degree. C. and 90.degree. C.