Longde        35°27.27’N, 105°56.50’E

Ningxia, China

Confirmed fall: 10 July 2022

Classification: Ordinary chondrite (L5)

History (Zhang Bo, Ma Rongwei, Li Shijie, Hsu Weibiao): On 10 July 2022, at 10:14 p.m. local time, numerous people from Longde, Huating, of Gansu Province witnessed a bolide and sonic booms. In the same evening, Mr. Wang Jialiang was fishing at Shatang Town of Longde city, Gansu Province. He saw two fireballs moving from northeast to southwest. At approximately the same time, Mr. Zhang, a local farmer in the Zhangdugou village, Wenbao Town, Longde city (about 15 km south to the fishing site), heard a sonic boom. As it was raining, Mr. Zhang did not check his yard at night. On the next day morning, Mr. Wang called and visited Mr. Zhang, and saw a dent (35°27’16.3"N, 105°56’30.3"E) on the driveway and numerous gray fragments spreading around the dent. Mr. Wang and Zhang collected all fragments in the backyard. At the suggestion of Mr. Ma Rongwei, a meteorite dealer, Mr. Wang donated 20 g specimen to PMO for classification. About 800 g of fragments were sold to several Chinese meteorite dealers on site. The remaining was in the possession of Mr. Wang. In the following days, several small fragments (mg up to 100 g) were recovered at roadside and field in the neighboring village, Caifanjia. At an undisclosed location, several kilometers southwest to the Zhangdugou village, an anonymous farmer heard a ballistic sound that night and noticed a huge hole on one of his houses next day morning. He recovered a single stone of 45 kg. Du Zhimao and Xiao Jiang from Shanghai Planetarium, Zhang Bo, Zhao Tailu, and Wang Weiwei, meteorite dealers, went for a field trip to Jingning City, Gansu province where the large stone could be supposedly located. Mr. Zhang Bo purchased the 45 kg stone at a highway station in Jingning city. Meanwhile LI Bin, LIAO Shiyong, and LI Ye from PMO went to the estimated strewn field in Jingning and Longde on 17 July for investigation and collected some surveillance videos from the police and gas stations. Seismic records were also taken from local seismic stations.

Physical characteristics: (Zhang Bo, Ma Rongwei, Hsu Weibiao) Fragments recovered at the Zhangdugou village weigh about 1200 g in total mass. They range from mm to cm in size and appear in grsy color. Some fragments retain partial fusion crust and bear metallic stains due to the rain. The large stone recovered in Jingning was 80% covered with fusion crust. Numerous cracks appear on its surface. One side is completely broken but bears some evidence of secondary fusion. Black to brown troilite grains are concentrated on a broken surface of the large stone. A small chip (5 g) was taken from the stone for investigation.

Petrography: (A. Mei, PMO): Petrographic and geochemical data were obtained at PMO on both samples collected from the Zhangdugou village and the large stone in Jingning. They exhibit essentially the same petro-chemical characteristics. Major silicates include low-Ca pyroxene (En_77.0±1.0Wo_1.5±1.0Fs_21.4±0.7), olivine (Fa_25.4±0.9), and albitic plagioclase (Ab_80.1±5.9An_13.3±5.9Or_6.5±3.4). Minor phases include kamacite, taenite, troilite, diopside (En_48.1±6.2Wo_43.3±8.7Fs_8.6±2.7), chromite, and phosphates. Mineral chemistry shows a high degree of equilibrium. A few poorly defined chondrules are recognized that include BO, PO, and PP chondrules. Plagioclase crystals mainly occur interstitially in the matrix and are generally smaller than 50 µm.

Geochemistry: (A. Mei, PMO): Olivine Fa_25.4±0.9, N=143, range Fa_23.8-29.6; Low-Ca pyroxene Fs=21.4±0.7, N=132, range Fs_18.8-25.1.

Classification: (A. Mei, PMO): Ordinary chondrite (L5). The texture and mineral chemistry are consistent with an L5 ordinary chondrite.

Specimens: 20 gram at PMO and 5 g at IGCAS