Notice: this meteorite was originally published here as "Rusalka." After review, the name has been changed to Northwest Africa13004.

Northwest Africa 13004 

Find: 2016 Mar

Classification: Ordinary chondrite (L4)

History: A fresh meteorite sample of 816 g.

Physical characteristics: The meteorite has a dark appearance with a well-preserved fusion crust.

Petrography: (A. Bischoff, IfP). The rock is an ordinary chondrite. It has a chondritic texture, with well-defined chondrules with a size of about 500 µm. The metal is well-preserved, but partly shows thin rims of typical terrestrial alteration products. The weathering degree is W1. The rock is weakly shocked with olivines having planar fractures (S3).

Geochemistry: Mineral compositions and geochemistry: (K. Klemm and A. Bischoff, IfP). The rock has equilibrated olivine (average: Fa_22.6±0.7; n = 10). Low-Ca pyroxene (average: Fs_17.9±2.2; (n = 9)) shows some variation in composition (range: Fs_13.9-19.7) typical for type 4 ordinary chondrites. The analysis of the oxygen isotopes (A. Pack, UGött) indicates an L chondrite heritage (δ¹⁸O=5.32‰, δ¹⁷O=3.51‰; Δ¹⁷O=0.74‰). The composition has been affected by terrestrial alteration. Cosmogenic radionuclide concentrations have been analyzed (M. Laubenstein, LNGS) by means of nondestructive high purity germanium (HPGe) gamma spectroscopy in spring 2019. Of the medium and long-lived cosmogenic radionuclides only ²²Na and ²⁶Al were positively identified. From the data, it was calculated that the meteorite probably fell about 12 (±2) years ago.

Classification: Ordinary chondrite (L4, S3, W1)

Specimens: 20.5 g and polished thin section