Ceramic Clays and Shales from the Melbourne Area. I. Mineralogy and Particle Size Distributions

摘要

A detailed analysis has been made of the mineralogy and particle size distributions of some ceramic clays and shales from the Melbourne area. Materials used for brick manufacture were taken from eight pits working in the weathered Silurian shales. Materials used for tile, hollow lumber, pipe, and extruded brick manufacture were taken from 13 pits working in clays developed by laterization of Silurian shales during lower Pliocene times. The unweathered blue Silurian shale is composed of quartz, muscovite, kaolinite, and chlorite with ocassional traces of siderite. As the shale weathers the kaolinite becomes disorganized, chlorite and siderite are destroyed and replaced by an interstratified mineral and goethite, respectively, quartz is unaffected, and muscovite is only slightly altered. There is very little difference in the mineralogical composition of commercial mixes prepared from the weathered Silurian shales and the laterized Silurian shales. (Author)