Nayak, V. K. and Leake, B. E. 1975. On 'winchite' from the original locality at Kajlidongri, India. Mineralogical Magazine 40 (312) , pp. 395-399. 10.1180/minmag.1975.040.312.08 |
Abstract
A new analysis of the violet amphibole from the original locality where winchite came from agrees with another recent analysis in differing substantially from the original winchite composition and is (K0·17Na2·10Ca0·23)(Al0·19Ti0·00Fe3 1·27Fe2 0·01Mn0·07Mg3·34)Si8·01O22·05(OH)1·95. It is essentially a magnesio-arfvedsonite. Although it is possible that the original analysis was unreliable, evidence is given to support the alternative view that there is a wide range of blue alkali and soda calcic amphibole compositions at Kajlidongri and the name winchite should be restricted to compositions between ferri-winchite CaNaMg5Fe3+Si8O22(OH,F,Cl)2 and alumino-winchite CaNaMg5Al Si8O22(OH,F,Cl)2. X-ray, density, and optical data on the analysed mineral are given.
Item Type: | Article |
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Date Type: | Publication |
Status: | Published |
Schools: | Earth and Environmental Sciences |
Publisher: | Mineralogical Society |
ISSN: | 0026-461X |
Last Modified: | 16 Jul 2020 10:15 |
URI: | https://orca.cardiff.ac.uk/id/eprint/133106 |
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