NEW DATA ON TOBERMORITE STRUCTURE. N.I. Organova,A.E.Zadov, N.V.Chukanov, O.V.Kuzmina, M.A.Lizarev, A. V.Mochov, N. V.Trubkin, Inst.of Ore deposits, Moscow, Russia.

Many tobermorite samples from the different deposits were investigated by different methods. According analitical electron microscopy and SAD there are chemical and defect ingomogenity in every sample. Several types of electron diffraction patterns have been observed. Except two twin planes (001) and (100) one can see also two satellite types on SAD (hkO) patterns that correspond to different periodic disturbances of perfect structure. IR-spectra of different calcium hydrosilicates have shown systematic displacemente of the main absorption band responsible for an anion type and its condensation degree. According this study plombierite and tobermorile have ribbon anions contrary to Iiterature ideas about chain ones. These facts and Hamid's tobermorite model were foundation for the model of its ribbon structure. The main idea is a possibility of two ways for condensation of three-membered silicium-oxigen chains to ribbon: one along [001] and other along [100].

We found a new monoclinic tobermorite variety with twice value of a axis in comparison with Hamid's, one and another monoclinic angle.

Hamid S. Zeitschr.f.Krist., 1981.

Zadov A.E., Chukanov N.V., Organova N.I. Zap.Miner, Obzh., 1995. (in Russian).