KAOLIN, BALL CLAY, OTHER CLAYS AND SHALE Indian Minerals Yearbook 2013 (Part- III : Mineral Reviews) 52nd Edition KAOLIN, BALL CLAY, OTHER CLAYS AND SHALE (ADVANCE RELEASE) GOVERNMENT OF INDIA MINISTRY OF MINES INDIAN BUREAU OF MINES Indira Bhavan, Civil Lines, NAGPUR – 440 001 PHONE/FAX NO. (0712) 2565471 PBX : (0712) 2562649, 2560544, 2560648 E-MAIL :
[email protected] Website: www.ibm.gov.in January, 2015 29-1 KAOLIN, BALL CLAY, OTHER CLAYS AND SHALE 29 Kaolin, Ball Clay, Other Clays and Shale 1. Kaolin (China Clay) PRODUCTION, STOCKS & aolin, also known as china clay, is a natural clay PRICES Kformed by chemical weathering of aluminium The production of kaolin at 3,679 thousand tonnes silicate minerals like felspars. It is relatively pure clay in 2012-13 increased by 20% as compared to previous predominantly consisting of kaolinite (Al2Si2O5(OH)4), year. associated with other clay minerals like dickite, There were 131 reporting mines during 2012-13 as halloysite, nacrite and anauxite. Kaolin is commercially against 105 mines in the previous year. Besides, the valued for its whiteness and fine particle size which production of kaolin was also reported as an associ- distinguish it from other clays, such as, ball clay and ated mineral by seven mines in the year 2012-13 and fireclay. Other physical characteristics that influence four mines in the previous year. Ten principal commercial utility include brightness, glossiness, producers accounted for about 70% of the total output abrasiveness and viscosity. It often contains small of kaolin in 2012-13. The private sector mines reported amounts of impurities in the form of rock fragments, 99.64% of the total production and the remaining 0.36% hydrous oxides and colloidal materials.