Cornish or China Stone. A rock composed of felspar and quartz. Its vitrification (about 1400 C.) im- parts hardness and density to China clays. It is a valuable constituent of glazes. First known as " moorstone " or " growan."
Cornish or China Stone. A rock composed of felspar and quartz. Its vitrification (about 1400 C.) im- parts hardness and density to China clays. It is a valuable constituent of glazes. First known as " moorstone " or " growan."