Paragonite Paragenesis from the Garnet Granulites of the Jijal Complex, Kohistan, N. Pakistan

M. Q. Jan, R. N. Wilson and B. F. Windley
Department of Geology, University of Peshawar, Peshawar, Pakistan
Department of Geology, The University, Leicester LE1 7RH, UK

Abstract: Chemistry of six white micas from the high-pressure garnet granulites of Jijal is presented, together with trace elements, refractive indices, and 2Vα for one. The micas are rich in the paragonite component (over 93%), with one analysis having the highest 100 Na/(Na + K) ratio (98.5) so far reported. The paragonite is not a stable mineral of the granulites but was over-printed on the granulites at about 505–540 °C and 8–9 kbar (suggesting a depth of 30 km).

Mineralogical Magazine; 1982 v. 45; no. 337; p. 73-77; DOI: 10.1180/minmag.1982.045.337.08
© 1982, The Mineralogical Society
Mineralogical Society (www.minersoc.org)