MOSSBAUER SPECTROSCOPIC STUDIES ON 3 DIFFERENT TYPES OF CROCIDOLITE FIBERS

Mossbauer spectroscopic studies have shown that the M1 cationic site i n native UICC crocidolite is populated by both ferric and ferrous ions , whereas the M2 and the M3 sites are exclusively occupied by ferric a nd ferrous ions, respectively. The detoxification of these fibres incr eased the ferric ion content al the M1 sites and formed a layer of fer ric ions on the surface of the fibres. The activation process on the o ther hand, increased the ferrous ion content of these sites. Activatio n also converted some of the ferric ions at the M2 sites into ferrous ions and produced some metallic iron on the surface of the fibres.