Abstract
SummaryA 250 µm olivine crystal in Sharps contains 1 to 5 µm insets identified by microprobe analysis as ferroan monticellite, spinel, and fassaite with average compositions: olivine (host), (Fe0·44Mg1·51Ca0·05) (Si0·99Al0·01)O4; ferroan monticellite, (Ca0·89Fe0·41Mg0·66) (Si1·00Al0·02)O4; spinel, (Fe0·41Mg0·59)(Fe0·063+Cr0·23Al1·69Si0·01Ti0·01)O4; and fassaite, Ca0.96(Fe0·01Mg0·59)(Al0·18Ti0·07Fe0·163+)(Si1·53Al0·47)O6. Textural and experimental data suggest early crystallization of spinel from a calcic olivine melt, exsolution of ferroan monticellite from the host olivine, and reaction of spinel and ferroan monticellite to form fassaite. The severe depletion of alkalies and silica in this crystal suggests it is a residue from vapour fractionation.
Subject
Geochemistry and Petrology
Cited by
16 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献
1. Fe-monticellite in serpentinites from the Happo ultramafic complex;Lithos;2020-11
2. Petrology, mineralogy, and P–T path of calc-silicate granulites and fassaite-marbles from the Paleoproterozoic Gour Oumelalen area (Central Hoggar, Algeria);Arabian Journal of Geosciences;2016-06
3. RELICS OF HIGH-TEMPERATURE CLINOPYROXENE ON THE JOIN Di CaTs WITH UP TO 72 mol.% Ca(Al,Fe3+)AlSiO6 IN THE SKARNS OF CICLOVA AND MAGUREAUA VATEI, CARPATHIANS, ROMANIA;The Canadian Mineralogist;2005-06-01
4. Fayalite and kirschsteinite solid solutions in melts from burned spoil-heaps, South Urals, Russia;European Journal of Mineralogy;2002-07-17
5. Larnitic kirschsteinite from the Kotakonda kimberlite, Andhra Pradesh, India;Mineralogical Magazine;1996-06