Chemical Variations in Members of the Fergusonite-Formanite Series

J. R. Butler and Hall Rosemary
Imperial College, South Kensington, London, S.W. 7.

Summary: Attention is drawn to anomalies in the nomenclature of the niobatetantalates, and the fergusonite series as used by Dana is renamed the fergusonite-formanite series. Chemical variations in this series are discussed with particular reference to H2O, Ca, Ti, Yt, individual lanthanons, Th, and U. Members of the series usually show heavy lanthanons exceeding light lanthanons but one specimen shows high Gd+Tb+Dy.

Mineralogical Magazine; March 1960 v. 32; no. 248; p. 392-407; DOI: 10.1180/minmag.1960.032.248.06
© 1960, The Mineralogical Society
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