We have been asked for sterile white clay.

Raw materials for pharmaceutical preparations or vracprodukten, as you mention them, are certainly not considered sterile. Some, such as Eosin, Bolus alba and talc, are even heavily contaminated with germs or spores. So We have to sterilize them and this can be done with different techniques. The simplest is heating at 180 ° C for 1 hour. Chemically, these products are stable and therefore we can employ such high temperature.