Ion-exchange resins [45] were also consolidated by HHP with the aim of reducing the volume of the radioactive waste. The recurring concept of synthetic rock was employed to produce artificial pollucite (a zeolite mineral (Cs,Na)2Al2Si4O12·2H2O used for Cs encapsulation) [102] and for consolidation of sepiolite (Mg4Si6O15(OH)2·6H2O) while maintaining its high surface area exceeding 150 m2 g–1 [103].