Aba Panu, 2018 Nigeria Fall, L3.6 Chondrite, Micromount

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On the afternoon of April 19, 2018, a large fireball exploded over Nigeria near the village of Aba Panu. The fall caused a major disturbance and many large stones fell around villages in the area. Samples of the fall were collected and analyzed at ASU. It was classified as a L3 with an estimated sub-type of L3.6. It has a chondrule-rich matrix with metal flecks and the stones have relatively fresh crust.

Refer to the photo. The black centimeter cube is shown for scale and is not included. You are purchasing a small fragment like the one shown. Your purchase will include a gemjar and ID label.

From the Meteoritical Bulletin entry on Aba Panu :

Aba Panu        8°16’55.83"N, 3°34’1.72"E

Oyo, Nigeria

Confirmed fall: 19 April 2018

Classification: Ordinary chondrite (L3)

History: On the afternoon of 19 April 2018, a large fireball detonated over the Nigerian state of Oyo. This fireball was recorded by NASAs Center for Near Earth Object Studies (CNEOS) as event 2018-04-19 14:02:27. The meteoroid entered at 20.9 km/s and detonated at an altitude of 30 km at 7.5’N, 3.6’E releasing a calculated total impact energy of 0.23 kt. Many stones fell between the villages of Ipapo (8°7’50.84"N, 3°30’34.58"E) and Tede to the north (8°33’21.49"N, 3°26’46.31"E). Stone were collected at multiple locations. The meteorite is named for the village of Aba Panu near the center of the strewn-field: multiple kg-sized stones were found in and around this village. Current total known weight is near 160 kg.

Physical characteristics: The stones are hard, range from 30 g to near 40 kg, rounded with broad poorly developed regmaglypts, and largely lacking fusion crust. Fusion crust is occasionally preserved within the shallow regmaglypts. Most stones are greyish green and show areas of rounded to angular light-colored clasts. Largest clast (5 × 2 cm) is angular, fine-grained, and achondritic. Observations from multiple slices show that clasts constitute roughly <10 areal%.

Petrography: Visually the cut surfaces are dominated by a gray matrix, studded with well-developed chondrules and chondrule fragments. Some chondrules to 4 mm but the majority are 0.1 to 1 mm across. Observations on an 8 × 7 cm slab shows the following clasts: L6 (3 × 1 cm); L5 (1.5 × 1 cm); and sub-rounded 1-cm dark clast with sparse 200 micron chondrules. Shock veins are rare. Metal and sulfide occurs as: fined grained spheres in the matrix; armoring chondrules; and, occasional lumps to 5 mm. Petrographic observations show a range of chondrule types dominated by PO, POP, RP, PP, and BO. Particularly evident in thin section are BO and PO chondrules with reddish purple (in plain polarized light) glass that is isotropic under crossed polars. The silicates are extensively shocked with olivine showing mosaicism and PDFs. SEM observations show that much of the metal/sulfide in the matrix occurs as fine-droplets, veins, and melt pods. Large Fe-Ni grains are polycrystalline with each crystal showing a kamacite core, dark-etched martensitic inner rim, and outer Ni-rich rim. Troilite is dominantly single crystal, and occasionally polycrystalline. Sparse chromite grains.

Classification: Geochemistry and oxygen isotopic data consistent with L chondrite. Estimated petrologic type 3.6 based on Fa and Fs spread, and Cr2O3 content in olivine. L3, S4, W0.