The formation of clays, types of clays and potter's earth, the techniques of shaping, decorating, and firing and especially the main grouping of ceramic products are discussed according to their technical characteristics: non-glazed earthenware, glazed earthenware, stoneware, pottery, porcelain. This article is intended to assist the conservator in classifying pottery. Bibliography for this is in No. 2/1975, group 4, pp. 58-59. R.W. (A.A.) -- AATA