Image dhofar 1285 1
Image dhofar 1285 2
Image dhofar 1285 3
History: Three dark brown stones, broken into fragments of total weight 406 g, were found on
11 December 2002 in the desert of Oman. The fragments were separated by ~2.5 km.
Petrography: (Lorenz, Vernad; Brandstätter, NHMV) A coarse-grained rock that consists
mainly of olivine with minor amounts of pyroxene. The veins of troilite and Fe,Ni metal crosscut
the whole rock. Accessory phases, graphite, and daubreelite are present.
Geochemistry: The cores of olivine grains (Fo76.6; Fe/Mn = 59) are surrounded by reduction
rims (~50 µm in width), which contain small Fe-rich metal grains. The composition of olivine
within the reduction rims gradually changes from Fo78; Fe/Mn = 51 on the inside towards
Fo96; Fe/Mn = 8.6 at the outer edge. The outer parts of the olivine grain rims are completely
replaced by a fine-grained aggregate of olivine (Fo97–99), troilite, and metal. Reduction zones
are developed along cracks and veins that cross-cut olivine grains. Pyroxene (En78.7Wo9.8;
Fe/Mn = 20) contains numerous, tiny, co-oriented inclusions of Ca-rich pyroxene (En56.2Wo37.
3; Fe/Mn = 13), SiO2-rich feldspathic (Ab50An48.5) glass, low-Ni Fe,Ni metal grains, and
extremely fine, poorly resolvable exsolution lamellae of Ca pyroxene. In places, pyroxene grains
also have reduction rims with composition En83Wo6.7. Cr2O3 contents of olivine and
pyroxene (0.7 and 1.1 wt% respectively) and CaO content of olivine = 0.4 wt% are in the
ranges of those established for ureilites.
Classification: Achondrite (ureilite); moderate shock, extensive weathering.
Specimens: A 92.48 g type specimen and one thin section are on deposit at Vernad. An
anonymous finder holds the main mass.
||Found 2002, Oman
|moderate shock, extensive weathering
||Polished thin section