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On September 13,1976,the Qingzhen enstatite chondrite fell near Qingzhen County,Guizhou Province(26°32′N,106°28′E).The total mass recovered was 2.6 kg.Phenomena ofthe meteorite fall were recorded as well.In the present paper some of the significant observa-tions are described.X-ray diffraction analyses and petrologic studies revealed that it ismainly composed of enstatite/clinoenstatite,plagioclase,troilite,kamacite,taenite,quartz andoldhamite.X-ray electron microprobe analyses were performed on orthoenstatite and clinoensta-tite.Chemical analysis gave:SiO_2——36.48;Al_2O_3——1.64;TiO_2——0.08;Cr_2O_3——0.28;FeO——0.30;MnO——0.25;MgO——18.19;CaO——1.14;Na_2O——1.06;K_2O——0.11;H_2O~+——0.47;H_2O~-——0.10;P_2O_5——0.39;FeS——13.35;FeO——22.94;Ni——1.81;Co——0.093;C——0.37;Cu——0.022;Zn——0.027;CaS——0.60;total——99.70(wt.%).This meteorite has been extremely reduced;all iron is present as FeS and metallic Fe-Ni.The Qingzhen enstatite chondrite is characterized by high ratio,Si/Mg as compared withordinary chondrites,scarcity of olivine,and enrichment in sulfur and iron.In thin sections,it is observed that round chondrules approximately account for 10—15 per cent,being por-phyritic,radial,excentroradial,or excentric fan-shaped.Devitrified chondrules composed ofpyroxene were also identified.It is postulated from its mineralogy,chemistry and texturalcharacteristics that the Qingzhen meteorite should be assigned to E_4 or EH chondrites.
On September 13, 1976, the Qingzhen enstatite chondrite fell near Qingzhen County, Guizhou Province (26 ° 32’N, 106 ° 28’E). The total mass recovered was 2.6 kg. Phenomena of the meteorite fall were recorded as well. The present paper some of the significant observa-tions are described. X-ray analysis analyzes and petrologic studies revealed that it is mainly composed of enstatite / clinoenstatite, plagioclase, troilite, kamacite, taenite, quartz and oldhamite. X- ray electron microprobe analyzes were performed on orthoenstatite and clinoensta-tite. Chemical analysis gave: SiO_2--36.48; Al_2O_3--1.64; TiO_2--0.08; Cr_2O_3--0.28; FeO - 0.30; MnO - 0.25; MgO - 18.19; CaO - 1.14; Na_2O - 1.06; K_2O - 0.11; H_2O ~ + - 0.47; H_2O ~ --- 0.10; P_2O_5--0.39; FeS - 13.35; FeO - 22.94; Ni - 1.81; - 0.37; Cu - 0.022; Zn - 0.027; CaS - 0.60; total - 99.70 (wt.%). This meteorite has been extremely reduced; all iron is present as FeS and metallic Fe-Ni.The Q ingzhen enstatite chondrite is characterized by high ratio, Si / Mg as compared with ordinary chondrites, scarcity of olivine, and enrichment in sulfur and iron. thin sections, it is observed that round chondrules approximately account for 10-15 per cent, being por- phyritic, radial, excentroradial, or excentric fan-shaped. Devitrified chondrules composed of pyroxene were also identified. It is postulated from its mineralogy, chemistry and textural characteristics that the Qingzhen meteorite should be assigned to E_4 or EH chondrites.