隕石深成 Angrite，Rafsa 007。 非常稀有，無底價 - 1.74 g

Rafsa 007 28.642936°N, 8.199231°W
Tindouf, Algeria
Purchased: 2023
Classification: Angrite
History: Reportedly several groups of Sahrawi meteorite hunters found several fragments of this meteorite in an area ~100 km north of Tindouf at the end of summer 2023.

Petrography: (K. Metzler, IfP) Ultramafic rock with granular texture, mainly consisting of Ca-rich olivine (up to several mm) which encloses Al-Ti-bearing diopside (up to ~1 mm) and small amounts of Cr-bearing pleonast spinel (up to ~0.5 mm) and anorthite. The latter frequently occurs as thin ( µm) rims around spinel grains. Accessories are Fe-Ni metal, troilite, and merrillite. Much of the metal has been terrestrially altered and forms thin veins crosscutting the entire rock.

Geochemistry: Mineral compositions and geochemistry: Olivine composition: Fa39.0±0.4 (Fa38.4-39.5); Fe/Mn (at.): 87.4; CaO = 1.0-1.3 wt%; n=13. Pyroxene composition: Fs10.7±0.6 Wo52.9±0.6 (Fs9.7-11.6 Wo51.8-54.0); Fe/Mn (at.): 52.9; Al2O3 (wt%) = 6.9-9.5; TiO2 (wt%) = 1.6-2.4; n =11. Feldspar composition: An99.4±0.5 Or0.0±0.0 (An98.5-100.0 Or0.00); n=12. Pleonast spinel: Mg/(Mg+Fe (at.) = 0.47-0.50; Cr2O3 (wt%) = 4.5-5.5; Al2O3 (wt%) = 56.9-58.6; n=14.
Classification: Plutonic angrite, based on mineral chemistry and texture.

Shock stage: U-S1
Weathering grade: Moderate
Classifier: K. Metzler, IfP
This lot comes with certificate of authenticity.
Thanks for your interest.