Ceramic raw materials in the Viterbo district

North Latium is characterized by widespread volcanic areas; at present we observe evidence of hydrothermal and fumarolic processes that often produce transformations in the original volcanites. As products of these changes we found new mineralogical phases together with original phases. Sometimes there are also modifications due to sintering reactions. We recognized Halloysite, Sanidine, Zeolites, Amorphous Silica, Smectite. The presence of sulphates like Alunite, Gypsum and Jarosite makes those minerals unsuitable for the ceramics industry. SIV (Viterbo's Industrial Society) promoted a joint research with the University of Modena to have a better knowledge on raw materials of the Viterbo's district. Known raw materials outcrops are described and new ones of Halloysite, Zeolites, Sanidine, Smectite and Amorphous Silica have been identified. The possibility of industrial use is discussed on the basis of Sulphates content.