Rare Earth Chemistry of Perovskite Group Minerals from the Gardiner Complex, East Greenland

Linda S. Campbell*, Paul Henderson, Frances Wall and Troels F. D. Nielsen
The Natural History Museum, Cromwell Road, London SW7 5BD, UK
Øster Voldgade 10, 1350 Copenhagen K, Denmark
*Present address: School of Geological Sciences, Kingston University, Penrhyn Road, Kingston upon Thames, Surrey KT1 2EE, UK.

Abstract: Perovskite group minerals, general formula ABX3, from the intrusive ultramafic alkaline Gardiner Complex, East Greenland, range from almost pure CaTiO3 (perovskite, sensu stricto), to the rare earth element (REE) variety, loparite-(Ce). Chemical zonation in the perovskites (sensu lato), is described by the substitutions 2Ca2+ = (Na++ REE3+) on the A-site and 2Ti4+ = (Fe3+ + Nb5+) on the B-site. Other trace elements detected include Th, Sr, Al, Si, Zr, Ta and Sn. Excellent agreement was found between the determinations of the REE by electron microprobe and neutron activation analysis. Chondrite-normalized REE patterns display enrichment in the light rare earths for perovskite, loparite, apatite, melilite and diopside. Mean perovskite/apatite partition coefficients from four of the Gardiner rocks were calculated as La = 10.4, Ce = 13.8, Nd = 13.9, Sm= 9.9, Eu = 7.7, Gd = 5.2, Tb = 5.6, Tm = 5.5, Yb = 2.7 and Lu = 1.6, indicating that perovskite concentrates all REE to a much greater extent than apatite. Light-REE enrichment occurs in both perovskite and apatite.

Keywords: rare earth elements • perovskite • apatite • loparite • Gardiner Complex • Greenland

Mineralogical Magazine; April 1997 v. 61; no. 405; p. 197-212; DOI: 10.1180/minmag.1997.061.405.04
© 1997, The Mineralogical Society
Mineralogical Society (www.minersoc.org)