Trace Element Distributions Between the Perthite Phases of Alkali Feldspars from Pegmatites

R. A. Mason*
Department of the Geophysical Sciences, University of Chicago, Chicago, Illinois 60637 USA
*Present address: Department of Earth Sciences, Bullard Laboratories, Madingley Rise, Cambridge CB3 0EZ.

Abstract: The distribution of various trace elements between the K-feldspar and albite phases of perthites from several pegmatites was determined by ion microprobe. Ranges in distribution coefficients (wt. % in K-feldspar/wt. % in albite) are: Li, 1.2–780; Mg, 0.2–1.1; P, 0.1–17; Ca, 0.02–1.6; Cs, 32–820; Ba, 24–284; Pb, 1.6–30; Fe, 0.3–0.7; Rb, 59–5505; Sr, 1.3–5.1. The trace elements are zoned within the K-feldspar lamellae and the profiles are interpreted as the result of cross coefficients in the diffusion matrix.

Mineralogical Magazine; 1982 v. 45; no. 337; p. 101-106; DOI: 10.1180/minmag.1982.045.337.11
© 1982, The Mineralogical Society
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