Abstract
Zeolite is micro-porous crystalline mineral having a highly regular structure of pores and chambers usually occupied by H2O molecules and extra-framework cations that are commonly exchangeable. The different zeolites differ in pore diameter and shape and the way these pores are interconnected. In this Chapter the basic principles of the natural zeolites framework and porosity are presented.
Keywords: Natural zeolites, structure, porosity, framework, building units, aluminosilicates.