Lunar Meteorite: Ghadduwah 001

from The Meteoritical Bulletin, No. 109

Ghadduwah 001

Awbari, Libya
Find: 2020 January 7
Mass: 265 g (1 piece)

Classification: Lunar meteorite (anorthosite)

History: This stone was found by vacationers on January 7, 2020, near Lake Gaberoun, Libya.

Physical characteristics: Single stone covered in pale-green, glassy fusion crust; oriented shape with a broad rollover lip. One side of the stone is broken and the interior is exposed, however this is not recent fracture as the surface is slightly weathered and smoothed. A freshly fractured surface shows a sugary, shiny texture of white to light gray grains.

Petrography:  (C. Agee, UNM) Microprobe and SEM reveals an anorthitic plagioclase host without visible grain boundaries making up ~92% of this meteorite. Poikiolitically enclosed in the plagioclase are olivine and pyroxene grains, most in the size range 100-300 μm, making up a total of ~7% of this meteorite. Olivine grains are very homogeneous, some with resorbed rims. Pyroxene grains have exsolution lamellae with coarser bands of low-Ca pyroxene and finer bands of augite. Accessory chromite was observed throughout. Fusion crust is ~75 μm thick.

Geochemistry: (C. Agee, UNM) Plagioclase An_98.1±0.8Ab_1.8±0.3Or_0.0±0.0, n=4; pyroxene Fs_30.5±6.2Wo_12.7±11.4, Fe/Mn=52±8, n=9; olivine Fa_40.9±0.3, Fe/Mn=88±3, n=6; fusion crust SiO₂=43.1±0.2, Al₂O₃=31.0±0.1, FeO=3.7±0.2, MgO=3.3±0.1, MnO=0.05±0.03, CaO=17.0±0.1, Na₂O=0.19±0.02 all wt%, n=5. Oxygen isotopes (K. Ziegler, UNM): 3 acid-washed fragments analyzed by laser fluorination gave δ¹⁸O= 5.810, 6.152, 5.852; δ¹⁷O= 3.038, 3.198, 3.042; Δ¹⁷O= -0.029, -0.050, -0.047 (linearized, all per mil, TFL slope=0.528).

Classification: Lunar ferroan anorthosite, unbrecciated. Olivine, pyroxene and plagioclase compositional values plot within the FAN suite field (after Warren, 1993).

Specimens: 20.6 g on deposit at UNM, Abdelhadi Aithiba holds the main mass.

Randy Says…

This meteorites is the first unbrecciated anorthosite from the lunar highlands.

More Information

Meteoritical Bulletin Database

Ghadduwah 001

References

Agee C. B., Ross A.J., Ziegler K., and Spilde M. N. (2021) Ghadduwah 001: Uniquely unbrecciated ferroan anorthosite lunar meteorite. 52nd Lunar and Planetary Science Conference, abstract no. 2314.