Kyanite family mineral resources

Aluminosilicate are widely distributed in the Earth's crust, but kyanite group mineral deposits known industrial value not much. At present, the industrial-scale mining deposit types include: hydrothermal alteration of secondary quartzite andalusite - corundum deposits; andalusite deposit in contact metamorphic rocks; kyanite regional metamorphic rocks quartz schist and gneiss - Sillimanite or sillimanite deposit. Alumina minerals deposits often associated with quartz, mica, feldspar, garnet, corundum, rutile, and chlorite associated, sometimes a certain amount of iron and sulphide minerals.

It is estimated that the reserves of kyanite in the world are about 100 million tons. The Karikut deposit in Bihar, India, is one of the largest deposits in the world, and the alumina content in the ore is very high. The superior grade Al ₂ O ₃ is 60% to 75%, which can be used in industry without beneficiation . Its reserves are about 1 million tons. The largest kyanite deposit in the United States is in the southeastern part of Virginia, Georgia, North Carolina, and South Carolina. The amount of kyanite minerals is at least 60 million tons. The deposit belongs to kyanite quartzite, schist and gneiss. The content of the spar in the ore of each deposit varies greatly. The content of kyanite in quartzite is generally 20%-30%, and the content in schist and gneiss. Only 5% to 15%.

The kyanite deposits with industrial exploitation value have also been found in Jiangsu, Hebei, Shanxi, Xinjiang and other places in China. The content of kyanite minerals in Xinjiang deposits is 25%-80%, and other places are about 15%-20%. the following. In addition, Canada, Australia, Kenya, Zambia, Romania and other countries have industrial types of kyanite deposits.

California and Nevada, USA, contain huge amounts of andalusite deposits, which are 75% to 80% rich in andalusite. Australia, Africa and the former Soviet Union also have andalusite deposits, and large-scale rich deposits have also been found in Henan, China. The world's andalumino reserves amount to 10 million tons.

India has huge sillimanite deposits, and there are industrial value sillimanite deposits in Northeast China, the United States, South Africa and Australia. The reserves of the world sillimanite deposits amount to about 100 million tons.

The chemical composition of some kyanite ore abroad is listed in Table 1.

Table 1 Chemical composition of some kyanite ore abroad (%)