The Pendennis Peralkaline Minette

A. Hall
Department of Geology, King's College, Strand, London WC2R 2LS

Abstract: The Pendennis minette has an exceptionally high K2O/Na2O ratio and is strongly peralkaline. Its constituent minerals, which are described in detail, are sanidine, biotite, two carbonates (dolomite and ferroan magnesite), two amphiboles (riebeckite and a new variety, potassium magnesio-arfvedsonite), and quartz. The major and trace dement composition of the minette indicates close affinities with the lamproitic lavas.

Mineralogical Magazine; 1982 v. 45; no. 337; p. 257-266; DOI: 10.1180/minmag.1982.045.337.29
© 1982, The Mineralogical Society
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