Crystal chemistry of the natural vanadium bronzes

H. T. Evans; J.M. Hughes

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USGS · 70015745

Crystal chemistry of the natural vanadium bronzes

H. T. Evans·J.M. Hughes

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Abstract

The crystal chemistry of the natural vanadium bronze minerals is reviewed on the basis of published information and new studies (mainly by X-ray powder-diffraction methods) using type material wherever possible. The known V bronze minerals are divided into three categories: 1) the hewettite group, 2) the straczekite group, 3) other structure types including navajoite, schubnelite, fervanite, shcherbinaite, bannermanite, and melanovanadite. All known structures associated with the fibrous V bronzes (fiber spacing 3.6 A??) can be considered as various lateral linkages (into sheets or networks) of only two types of polyvanadate chains: 1) a divanadate chain (V2O6)n consisting of alternating square pyramids, and 2) a tetravanadate chain (V4O12)n consisting of four highly condensed single octahedral chains. -from Authors

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H. T. Evans, J.M. Hughes. 1990. Crystal chemistry of the natural vanadium bronzes. https://pubs.usgs.gov/publication/70015745

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