Results
Title

New morphological, chemical, and structural data of woolly erionite-Na from Durkee, Oregon, U.S.A.

Authors

CAMETTI, GEORGIA; PACELLA, ALESSANDRO; MURA, FRANCESCO; ROSSI, MARCO; BALLIRANO, PAOLO

Abstract

detailed morphological, crystal-chemical, and structural characterization of erionite from the type locality of Durkee, Oregon, has been carried out by combining field emission scanning electron microscopy (FESEM) and laboratory parallel-beam transmission X-ray powder diffraction (XRPD). According to the crystal-chemical formula (Na5.38K1.99Mg0.24)[Al7.66Si28.34O72.09]⋅29.83H2O, the sample has been classified as erionite-Na. The Rietveld refinement has indicated that the extraframework cations are located at three Ca1, Ca2, and Ca3 sites, the first one containing all available Mg. Moreover, the absence of the additional K2 site found in both dehydrated erionite and erionite-K has been demonstrated for this erionite sample. Furthermore, our results revealed the absence of Fe and Ca although previous investigations have reported the presence of a variable content of both these elements in erionite samples from Durkee. This is relevant information because it is well known from amphibole asbestos that Fe2 has been claimed to be one of the causes of carcinogenesis by participating in Fenton chemistry and producing free radicals.

Subjects

MINERALS; CRYSTAL structure research; RIETVELD refinement; SCANNING electron microscopy; X-ray powder diffraction

Publication

American Mineralogist, 2013, Vol 98, Issue 11/12, p2155

ISSN

0003-004X

Publication type

Academic Journal

DOI

10.2138/am.2013.4474