Northwest Africa 13739 (NWA 13739)

Tindouf, Algeria

Purchased: 2020

Classification: Lunar meteorite

History: Many fragments weighing a total of 712 g were found near Tindouf, Algeria, by locals. Carlos Muñecas (Expometeoritos) and Adrian Contreras purchased these samples from a dealer in Tindouf in November 2020.

Physical characteristics: Samples are irregularly shaped and lack fusion crust. Most samples are covered with a coating of caliche that also occurs within the interior of the samples in fractures. The interior is a dark-colored, fine-grained breccia.

Petrography: Description and classification (A. Love, App) Sample is a complex breccia composed of fine-grained (250 µm avg.) lithic and olivine, low- and high-Ca pyroxene, pigeonite and mineral fragments: gabbroic clasts, brecciated feldspathic clasts, FeNi metal and rare symplectites composed of fayalitic olivine and silica. This assemblage is crosscut by a several generations of crosscutting melt veins. Additional Minerals are sulfides, chromite, ilmenite, rare phosphates and secondary calcite.

Geochemistry: Microgabbro: olivine (Fa_30.0±8.9, Fe/Mn=80.4±10.2, n=12); low Ca pyroxene (Fs_24.7±2.1Wo_4.1±0.6, Fe/Mn=55.6±6.5, n=5); Mineral fragments: pigeonite (Fs_30.9±6.2Wo_12.0±5.0, Fe/Mn=52.9±4.2, n=15); high Ca pyroxene (Fs_43.6±16.2Wo_27.4±4.8, Fe/Mn=56.7±7.6, n=6); plagioclase (An_96.8±0.9Or_0.1±0.1, n=15).

Classification: Lunar (feldspathic breccia) Based on textures and mineral compositions, this sample is a lunar feldspathic breccia.

Specimens: Carlos Muñecas (Expometeoritos) holds the 228 g main mass and Adrian Contreras and Carlos Muñecas jointly hold the remaining 484 g. Eleven small fragments weighing a total of 23.47 g and a polished thin section are on deposit at App.