Dhofar 303

Oman

Found 2001 June 28

Lunar meteorite (anorthositic impact melt conglomerate)

A light grey stone weighting 4.15 g was found in the Dhofar region of Oman. Mineralogy and classification (M. Nazarov, Vernad; L. Taylor, UTenn): fusion crust is absent; meteorite has a typical conglomerate texture; rounded lithic clasts are cemented by a very fine-grained impact melt matrix; clasts of impact melt breccias are most abundant and show commonly breccia-in-breccia textures; primary igneous rocks and granulites are rare and have mainly anorthositic and troctolitic compositions; feldspar, An_94–99; orthopyroxene, Wo_1–5En_19–89; clinopyroxene, Wo_6–46En_29–70; olivine, Fo_48–88 (Fe/Mn ≈ 87 atom%); accessory minerals are Ti-rich chromite, ilmenite (3–6 wt% MgO), Al-Cr-Zr-rich armalcolite, rutile, troilite, and FeNi metal (1–37 wt% Ni; 0.2–2.3 wt% Co); composition of the impact melt matrix is SiO₂ = 44.0, TiO₂ = 0.15, Al₂O₃ = 29.8, Cr₂O₃ = 0.06, FeO = 3.17, MnO = 0.06, MgO = 4.91, CaO = 17.0, Na₂O = 0.34, K₂O = 0.01, P₂O₅ = 0.03 (wt%); the stone is moderately weathered; celestite, barite, gypsum, calcite and Fe hydroxides are present. The conglomerate texture and degree of weathering distinguish Dhofar 303 from Dhofar 302 and Dhofar 081/280, which were found nearby.  However the meteorites may be paired. Specimens: type specimen, 0.85 g plus a thin section, Vernad; main mass with anonymous finder.