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THE COMPOSITION OF THE JOHNSTOWN METEORITE
Meteoritics, 1971A new analysis of the Johnstown meteorite, a hypersthene achondrite, gives the following results (weight percent): SiO2 53.48, TiO2 0.12, Al2O3 1.43, Cr2O3 0.83, FeO 15.63, MnO 0.54, MgO 25.87, CaO 1.40, Na2O 0.04, K2O 0.00, P2O5 0.00, H2O+ <0.1, H2O‐ 0.05, Ni <0.05, Co <0.01, FeS 1.18, sum 100.57.
Brian Mason, E. Jarosewich
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THE CHEMICAL COMPOSITION OF METEORITES
International Geology Review, 1960At present, investigations on the chemical composition of meteoritic matter are being made in two directions: 1) the determination of the main constituents of meteorites of different classes. (A generalization of these data led to the classification of meteorites depending on their chemical composition); 2) the determination of all the element contents
A. A. Yavnel, M. I. Dyakonova
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The Composition of Meteoritic Matter: I. The Composition of the Silicate Phase of Stony Meteorites
The Journal of Geology, 1947A statistical study has been made of the analyses of the silicate phases of 107 selected stony meteorites. Frequency-distribution curves have been plotted, and arithmetic means, together with standard deviations and precisions, have been calculated for the major constituents.
Harrison Brown, Claire Patterson
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Presolar Grains in Meteorites and Their Compositions
Space Science Reviews, 2007Small amounts of pre-solar “stardust” grains have survived in the matrices of primitive meteorites and interplanetary dust particles. These grains—formed directly in the outflows of or from the ejecta of stars—include thermally and chemically refractory carbon materials such as diamond, graphite and silicon carbide; as well as refractory oxides and ...
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The Journal of Geology, 1938
Convincing evidence has been found that the generally accepted ideas regarding the average composition of meteorites are incorrect, owing to the fact that collections have not been completely representative.
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Convincing evidence has been found that the generally accepted ideas regarding the average composition of meteorites are incorrect, owing to the fact that collections have not been completely representative.
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Isotopic composition of silicon in meteorites
Geochimica et Cosmochimica Acta, 1986Abstract Samples of bulk meteorites show only mass-dependent fractionation of silicon isotopes. No isotopic anomalies were found. The variation of the ratios 29 Si/ 28 Si and 30 Si/ 28 Si over the meteorite classes is small; 1%. per mass unit difference.
Carol Molinivelsko +2 more
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Isotopic composition of meteoritic thallium
Earth and Planetary Science Letters, 1969Thallium contents have been determined as 2.5 ± 0.5 × 10−6 in Ivigtut, Greenland, galena; 7 ± 2 × 10−10 in Plainview chondrite; 1.5 ± 0.3 × 10−9 in Canyon Diablo troilite; and 2.5 ± 0.5 × 10−10 in Canyon Diablo metal. The205Tl/203Tl ratio is identical within about 0.6% of that of terrestrial thallium reagent, thus yielding no indication of extinct ...
R.G. Ostic, H.M. El-Badry, T.P. Kohman
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The amphoterites and meteorites of similar composition
Geochimica et Cosmochimica Acta, 1964Abstract The amphoteritos are a subclass of the olivine-hypersthene chondrites characterized by comparatively iron-rich olivine (Fa27–31) and orthopyroxene (Fs23–27) and a low content (1–5%) of nickel-iron. Other minerals include plagioclase (composition around An10), troilite, chromite and a phosphate mineral (apatite and/or merrillite).
Brian Mason, H.B. Wiik
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The isotopic composition of krypton in meteorites
Journal of Geophysical Research, 1964The isotopic composition and amounts of krypton extracted from four stone meteorites and one sample of meteoritic troilite have been measured. For the two chondrites Bruderheim and Abee, and the troilite phase of Canyon Diablo, the isotopic composition of krypton was found to be different from the isotopic composition of krypton in the atmosphere.
W. B. Clarke, H. G. Thode
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