Dhofar 307

Oman

Found 2001 April 14

Lunar meteorite (anorthositic impact melt breccia)

A light-grey stone weighing 50 g was found in the Dhofar region of Oman. Mineralogy and classification (M. Nazarov, Vernad; L. Taylor, UTenn): fusion crust is absent; the meteorite is an impact melt breccia; fine-grained impact melt is most abundant; mineral fragments and rare lithic clasts of anorthositic, troctolitic, and gabbro-noritic compositions occur in the impact-melt matrix; the presence of rare dunite fragments is a characteristic feature of the meteorite; glass veins are common; feldspar, An_89–98; orthopyroxene, Wo_1–5En_50–90; clinopyroxene; Wo_6–48En_40–75;, olivine, Fo_38–94 (Fe/Mn = 92 at); accessory minerals are Ti-rich chromite, Cr-pleonaste, ilmenite (2–6 wt % MgO), troilite, and FeNi metal (8–49 wt% Ni, 0.3–2.0 wt% Co); composition of the glass veins is SiO₂ = 43.8, TiO₂ = 0.09, Al₂O₃ = 30.8, Cr₂O₃ = 0.09, FeO = 2.58, MnO = 0.05, MgO = 4.06, CaO = 17.3, Na₂O = 0.36, K₂O = 0.01, P₂O₅ = 0.02 (wt%); the stone is moderately weathered; calcite, gypsum, celestite, barite, and Fe hydroxides are present. Dhofar 307 is similar in texture and mineral chemistry to Dhofar 305, found nearby. The meteorites are likely to be paired. Pairing with Dhofar 081/280, 302, 303, and 306 is also possible. Specimens: type specimen, 10 g and thin section, Vernad; main mass with anonymous finder.