Primary Baddeleyite (ZrO2) in Kimberlite from Benfontein, South Africa

D. E. Scatena-Wachel and A. P. Jones
Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, USA
Department of the Geophysical Sciences, The University of Chicago, Chicago, Illinois 60637, USA

Abstract: Baddeleyite was found during an electron microprobe study of kimberlite from the Benfontein Sills, which are famous for their igneous carbonate and cumulus features. Based on its close textural association with both groundmass and cumulus oxides (spinels, ilmenite, perovskite), the baddeleyite appears to be primary and crystallized directly from the kimberlite magma. The baddeleyite is remarkably pure, with average ZrO2 and HfO2 of 96.4±1.3 and 1.72±0.08 wt. % respectively. Minor element ranges found were: TiO2 0.32–0.80, CaO 0.31–0.80, FeO 0.43–1.31, MgO 0.06–0.24, SiO2 0.04–0.19, Cr2O3 0–0.07, and Al2O3 0–0.10 wt.%. Several additional trace elements were sought (Ce, Cs, Mn, Nb, Nd, Sr, Y, Yb, and U) but were not detected.

Mineralogical Magazine; June 1984 v. 48; no. 347; p. 257-261; DOI: 10.1180/minmag.1984.048.347.10
© 1984, The Mineralogical Society
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