Tapiolite, Its Chemistry and Cell Dimensions

A. M. Clark and E. E. Fejer
Department of Mineralogy, British Museum (Natural History), Cromwell Road, London SW7 5BD

Summary: Electron-probe analyses and cell dimensions are reported for twenty members of the tapiolite group. The minerals can be placed in ordered and disordered structural groups, the latter with a significantly larger c dimension. The a and c dimensions for both groups are dependent mainly on their titanium contents. The disordered set form part of a discontinuous series through strüverite/ilmenorutile to rutile. The chemical and structural data are incompatible with the existence of ferrotantalite or mossitc as valid species.

Mineralogical Magazine; December 1978 v. 42; no. 324; p. 477-480; DOI: 10.1180/minmag.1978.042.324.09
© 1978, The Mineralogical Society
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