Bentonites are characterised by many specific properties, e.g.: high ion exchange capacity, compliance to water dispersion, excellent sorption properties, strong swelling in polar liquids, and high tixotropy. These properties determine the mineral commercial applications in a wide range of markets, including: foundry, drilling, civil engineering, agriculture, ceramics etc. In Poland bentonites were mined temporarily: up to 1975 - from the Chmielnik and the Trepcza deposits, in the years 1966-1992 - in Hard Coal Mine Milowice (later called Czerwona Gwardia, and finally - Saturn), 1962-1987 - from the Chmielnik-Ciecierze deposit, and 1991-1996 - from the Krzeniów deposit. At present, almost all the raw bentonite supply in Poland originates from abroad. For many years these deliveries have been dominated by the Slovak Republic (45-77%). The raw material has come primarily from one of the largest deposit of bentonite in Europe - Jelsovy Potok. The deposit is mined for the most priced white bentonite, which is characterised by low content of iron oxide (2,0-2,8% Fe₂0₃). Raw bentonite is imported to Poland, primarily by the ZGM Zębiec near Starachowice and ZCh Siarkopol of Tarnobrzeg, and domestically processed mechanically and by chemical activation. Other important suppliers are Ukraine and Italy, most recently joined by India. High-grade bentonites are mainly purchased from Germany (products of the Süd Chemie AG) and from the United Kingdom.