Kaolinite's a clay mineral with the chemical composition Al2Si2O5(OH)4. It's a layered silicate mineral, with one tetrahedral sheet linked through oxygen atoms to one octahedral sheet of alumina octahedra. Rocks that're rich in kaolinite are known as china clay or kaolin. The name's derived from Gaoling or Kao-Ling ("High Hill") in Jingdezhen, Jiangxi province, China. Kaolinite was first described as a mineral species in 1867 for an occurrence in the Jari River basin of Brazil. Kaolinite's one… (More on Kaolinite)