Yagi K. et al. (1987) Petrology and Magnetic Properties Of Chiang Khan, Thailand, Meterorite (Meteoritics 22-4, 1987, pp. 536-537):
Chiang Khan meteorite fell on Nov. 17, 1981 at Chiang Khan, Loei, Thailand. The meteorite consists of olivine, orthopyroxene, clinopyroxene, chromite, FeNi metal, plagioclase, glass, troilite, and phosphate in order of abundance. Olivine always forms barred or porphyritic chondrules. Its composition is very homogeneous with an average of Fo80, which is very close to the average com- position of olivine of equilibrated H chondrites (Van Schmus, 1969). Orthopyro- xene usually forms radiating chondrules as fibrous crystals, whereas clinopyroxene is much less, occurring as fibrous crystals in the devitrified glass or minute crystals in the rim of orthopyroxene. Both orthopyroxene and clinopyroxene have compositions similar to those of these pyroxenes of equilibrated H chondrites (Van Schmus, 1969). Ca-poor pyroxene is nearly always orthopyroxene and clinoenstatite is almost absent. Plagioclase is present as microcrystalline aggregates only in a groundmass of chondrules. Chondrules are present, showing their textures well, but their outlines are often not clear. Glass is more or less devitrified, resulting in aggregates of fibrous or microcrystals. The composition of these aggregates is similar to that of Ca-rich pyroxene + albitic plagioclase. When compositions of chromite are plotted in a diagram Mg/(Mg +Fe) vs. Al/ (Al + Cr), all of them fall in the field of H chondrites (Bunch et al., 1967). From these features the meteorite is classified as an equilibrated chondrite of H5 type (Van Schmus and Wood, 1967). Water content and magnetic properties were measured. Bunch T.E., Keil K., and Snetsinger K.G. (1967) GCA 31, 1569-1582. Van Schmus (1969) Earth Sci. Rev. 5, 145-184. Van Schmus WR. and Wood J.A. (1967) GCA 31, 747-765. ______________________________________________ http://www.meteoritecentral.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
