Szakáll Sándor - Jánosi Melinda: Minerals of Hungary (Topographia Mineralogica Hungariae 4. Miskolc, 1996)

rocks which bear kaolinite, illite, and montmorillonite. Quartzites, associated with these, also contain industrially useful zeolites such as mordenite and clinoptilolite. The finest clays are used for ceramic purposes and, in its early years, the porcelain factory at Hollóháza (previously at Telkibánya) used local kaolinite for the manufacture of its products. Zeolite tuffs are used in agriculture and in the chemical, food, pharmaceutical and cosmetic industries. Fig. 18 OPAL (10 cm sp) Nagyhuta