Chemistry of levynes and epitaxially overgrown erionites

This paper deals with the chemistry of 12 levyne-erionite intergrowths. The two zeolite species differ for both framework and extraframework cation contents being levyne constantly Si-and K-poorer and Ca-richer than overgrown erionite. The relative increase of K in the parent solution during the crystallization process is considered the main responsible for the growth of erionite instead of levyne. The dominance of Na among extraframework cations in both levyne and overgrown erionite crystals of three samples of sea-shore occurrence is justified with later cation exchange with sea-water.