'CORRENSITE-L IKE MINERALS ' IN THE TARO AND CENO VALLEYS, ITALY

ABSTRACT: Mineralogical properties (XRD, DTG) and chemical compositions of some chlorite-smectite interlayer minerals inalteration products of ophiolitic rocks from the Northern Apennines are presented and discussed. The presence of iron hydroxides and the continuous variation i A1203 content suggest that the corrensites are intermediate stages in the process of alteration of chlorite to smectite in an environment characterized by high element mobility. A thermal test o characterize the swelling component of the interlayer species i proposed. Lippman (1954)first used the term 'corrensite ' to describe a regular 1:1 trioctahedral chlorite/swelling-chlorite nterlayer mineral, but subsequently showed that the swellin