Calc-aluminous insets in olivine of the Sharps chondrite
- 1 December 1971
- journal article
- Published by Mineralogical Society in Mineralogical Magazine
- Vol. 38 (296), 451-458
- https://doi.org/10.1180/minmag.1971.038.296.07
Abstract
Summary: A 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.Keywords
This publication has 14 references indexed in Scilit:
- Minor-Element Distribution in OlivineThe Journal of Geology, 1970
- Ca-Al rich phases in the allende meteoriteEarth and Planetary Science Letters, 1970
- The Major-Element Composition of Individual Chondrules of the Bjurböle MeteoritePublished by Springer Nature ,1969
- On the Formation of Chondrules and Metal Particles by ‘Shock Melting’Published by Springer Nature ,1969
- Empirical Correction Factors for the Electron Microanalysis of Silicates and OxidesThe Journal of Geology, 1968
- Chondrules: Suggestion Concerning the OriginScience, 1966
- Genesis of chondritic meteoritesReviews of Geophysics, 1966
- On the origin of chondrules and chondritesIcarus, 1963
- Kirschsteinite, a natural analogue to synthetic iron monticellite, from the Belgian CongoMineralogical Magazine and Journal of the Mineralogical Society, 1957
- Aluminous Pyroxenes in Metamorphosed LimestonesGeological Magazine, 1938