Description
I found this meteorite in Oman.
JaH 846 is an unequilibrated Type 3 chondrite with a range in olivine compositions from Fa0.6 to Fa38.1, as well a much lower magnetic susceptibility (logX = 4.91(10-9)m3/kg)
A really unique chondrite with some specific features.
Jiddat al Harasis 846 (JaH 846) 19.839°N, 55.870°E
Al Wusta, Oman
Find: 2011
Classification: Ordinary chondrite (type 3)
History: Found by an anonymous prospector in Oman in 2011.
Petrography: (A. Irving and S. Kuehner, UWS) Separated, well-formed, medium-sized chondrules (apparent diameter 560±380 µm, N = 40; some up to 2.2 mm) in a finer grained matrix. Minerals are olivine, orthopyroxene, clinopyroxene, sodic plagioclase, silica polymorph, chromite, troilite and altered kamacite. Some chondrules are devoid of olivine and are composed predominantly of orthopyroxene + a silica polymorph.
Geochemistry: Olivine (Fa0.6-38.1; Cr2O3 in ferroan olivine 0.04-0.22 wt.%, mean 0.08 wt.%, sd 0.06 wt.%, N = 9), orthopyroxene (Fs1.9-35.2Wo0.5-4.4, N = 3), clinopyoxene (Fs6.0-6.1Wo43.6-44.8, N = 2). Oxygen isotopes (K. Ziegler, UNM): analyses of 7 acid-washed subsamples by laser fluorination gave δ17O 4.988, 3.882, 4.098, 4.396, 4.262, 4.762, 4.838; δ18O 8.668, 6.724, 6.533, 7.237, 6.999, 8.155, 8.124; Δ17O 0.411, 0.332, 0.649, 0.575, 0.567, 0.456, 0.549 per mil. Magnetic susceptibility log χ (× 10-9 m3/kg) = 4.91.
Classification: Ordinary chondrite (OC3). Unusual features of this specimen include chondrules dominated by orthopyroxene + a silica polymorph, oxygen isotopic compositions closer to the TFL than for typical ordinary chondrites with similar degree of desert weathering and extending to very high δ18O values.
Specimens: Type specimen plus one polished thin section are at PSF; main mass with the anonymous finder.
