Abstract
Two kaolin deposits, one from New Zealand and the other from Australia, have been described with reference to the occurrence, the geology and mineralogy, the mining output, the quality as the raw materials for whitewares, the economical (or trading) aspects, etc. The clays from both deposits contain only a little Fe2O3 and TiO2 and, so, are best suitable for obtaining whitewares of good quality.
1. New Zealand kaolin
The mine is located in Matauri Bay area, Northland, owned by New Zealand China Clays Ltd. The kaolin deposit was formed by hydrothermal alteration followed by weathering, and is composed of halloysite and quartz, with some amounts of cristobalite and feldspars. The latter three minerals are removed effectively, and the clay material (<2μm halloysite) is concentrated up to 98% on the dry matter basis.
2. Australian kaolin
The mine is located in Greenbushes Mineral Field, in the southwest of W. Australia, owned by Greenbushes Tin Ltd. The deposit was formed by weathering of feldspars in pegmatite body, and is composed of kaolinite and quartz, with muscovite and feldspars as accessory components. The deposit is exported to Japan just as mined.