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
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