The trade of pottery was practised already in antiquity. This very old art had culmination points of its artistic performance in several epochs. The ornamentation of the body of the ware by glazing came in use in Germany (Rhine Territory) in the 12th century. The raw material applied were plastic argils baking with colour, at that time just as now. After dressing with water the plastic material was shaped to the most different objects. It was done, either off-hand or by the aid of the potter's wheel. Dust is developing when the argils are crushed representing a danger to health if technical control of the dust is not made effective. Wearing respiratory protection apparatuses is sufficient in shorttime work but must be regularly checked according to our experience. In the production of earthenware relatively high concentrations of dust occur only temporarily, but in very few cases they may cause silicosis. Among the 35 cases of silicosis in potters observed by the different special services for prophylaxis and control of dust 25 developed by exposition in plants of the GDR. 8 of the 10 diseased persons with exposition in plants outside the GDR had worked as potters in Bunzau (Silesia). The danger of silicosis is by for less than in the porcelain industry; it can be prevented by keeping clean the places of employment. This low danger is proven also by the very long exposition time of 30--40 years in average.