| 摘 要： | Principal transparent minerals in the Jilin meteorite include forsterite (Fa 17.8--19.5), orthopyroxenes (mainly Fs 14.1-15.8), clinopyroxenes (clinobronzite, diopside and pigeonite), plagioclase (An 8--12), orthoclase and whitlockite. Among the 17 accessory and minor minerals recognized are: tremolite, zircon, sodalite, calcite, siderite,moissanite, quartz, christobalite and rutile. The chemical composition of olivine is relatlvely uniform. Of pyroxenes orthopyroxenc predominates while clinopyroxenes are rare. Optical measurement indicates a limited compositional variation for orthopyroxene. Feldspars occur mainly as microcrystals and glass chondrules have mostly devitrified into crystallites, microcrystals or even to perfect crystals. The outline of chondrules is partly clear or, in some cases,merely recoguizable. The Jilin meteorite should belong to the type of 4-5, basically type H 5, in accordance with the petrochemical classification suggested by W. R. van Schmns in 1967.
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