Section 05 Mineral products 25 Salt, sulphur; earths and stone; plastering materials, lirne and cement 25 12 Siliceous fossil meals (for example, kieselguhr, tripolite and diatomite) and similar siliceous earths, whether or not calcined, of an apparent specific gravity of 1 or less Commodity Code Description 25 12 00 Siliceous fossil meals (for example, kieselguhr, tripolite and diatomite) and similar siliceous earths, whether or not calcined, of an apparent specific gravity of 1 or less.