Tubular clays

摘要

VERY MUCH THE little brother for kaolin, halloysite (Al_4(Si_4O_(10))(OH)_8 centre dot 4H_2O, differs in that it usually contains water molecules between the two-layer aluminosilicate structural units - a similarity to the major smectite group mineral, montmorillonite. This water is easily removed to yield a dehydrated form of halloysite. Because of the considerable difference in ionic size between aluminium and silicon in this two-layer structure, directional bending of the silica layer occurs.