The similarities and differences among the highly siliceous sintered products produced in Egypt, Asia, and Europe over a period of over 3000 years are presented. The chemical compositions of these materials agree to a large extent. The differences in composition are attributed to the variations in the raw materials. Two possible ways of manufacture of these materials are: (1) use of lime containing sand and natural soda, (2) addition of glass powder to finely powdered sand. In view of the similarities of structures (as indicated by thin section examination); the names of the places of origin are used to distinguish materials from different places, e.g., Egyptian-, Asian-sintered products (silica ware). -- AATA