Dhofar 733 & 1766
733 in the field
credit: anonymous finder)
very small block of Dhofar 733
credit: Randy Korotev)
1766 in the field
credit: anonymous finder)
faces of 2 slices of Dhofar 1766. Millimeter ticks for scale. The
lightest-colored regions are vesicles filled with terrestrial alteration
minerals like gypsum and celestite. Click on image for enlargement.
of a thick (100 µm, top) and thin (35µm, bottom) section of Dhofar 1766.
Maximum width: 12 mm.
Bulletin, No. 87, Meteoritics
& Planetary Science 38,
Found: 2002 November 12
Mass: 98 g
(anorthositic granulitic breccia)
brownish grey stone weighing 98 g was found in the Dhofar region of Oman.
and classification (S. Demidova, Vernad;
MNHV): fusion crust is absent; the rock contains relics of mineral and lithic
clasts and shows granoblastic or poikiloblastic textures; anorthositic,
troctolitic and gabbro-noritic lithologies are present.
compositions: feldspar, An89-96;
orthopyroxene, Wo4-5En73-76; clinopyroxene, Wo36-40En48-52;
olivine, Fo71-76 (Fe/Mn ~87 at). Accessory minerals are
armalcolite, ilmenite, Al-Chromite, Ca-phosphate, troilite, and FeNi metal
(31-43 wt% Ni; 1.3-1.7 wt% Co); lath-shaped armalcolite is most common; the
stone is moderately weathered; smectite, gypsum, and Fe hydroxides are present.
Dho 733 was found far away from other lunar stones collected in the Dhofar
region and has a distinctly different texture. It is probably not paired
with any other Dhofar lunar finds known so far.
type specimens of 20 g, and a thin section, Vernad;
main mass with anonymous finder.
The Meteoritical Bulletin, No.
Found: 2011 December 9
Mass: 292 g
Lunar meteorite (feldspathic breccia)
by a prospector in December 2011.
characteristics: Angular 5 × 4 × 3 cm stone (292 g) with
shiny, reddish exposure surface and bluish-grey basal surface. On surface
~5 mm rounded, knobby, yellowish-white to dark grey, partly melted clasts
are embedded in a flow-textured groundmass, which has abundant, sub-mm
Wittmann and P.Carpenter, WUSL) Melt
rock with flow texture of aphanitic melt enclosing 5 to <0.5 mm size
clasts of feldspar-rich rocks. All clasts are recrystallized but retain
outlines of original textures of poikilitic to subhedral mafic silicates in
plagioclase-dominated groundmass. Groundmass plagioclase forms dense masses
of tabular, felty textured crystals with <10
µm skeletal pyroxene crystals filling interstices. Olivine occurs up to 50
µm, zoned, subhedral crystals in the melt groundmass, and in partly
assimilated clasts is overgrown with augite that poikilitically encloses
acicular plagioclase, silica-rich mesostasis and euhedral, up to 30 µm
armalcolite crystals. Accessory troilite occurs in the melt groundmass as
round to oval, <10 µm crystals, some of which are intergrown with minute
taenite and tetratenite grains; subhedral to
granular, 30 to 250 µm chromian spinel crystals exhibit variable ° of decomposition
and recrystallization. Abundant vesicles are hollow or occupied by
secondary gypsum, celestite, rare barite, and greenish-yellow, Mg-rich
phyllosilicates (talc?) that are rimmed by celestite.
N=21); olivine (Fa10-30, molar Fe/Mn=61-195; N=20); augite (Fs10-21Wo24-42,
molar Fe/Mn=34-40; N=3); armalcolite (up to 0.4 wt% ZrO2; n=6);
; n=3), troilite (up to 0.3 wt.% Ni; N=3), metal (36.5-45.5 wt% Ni, 1.3-1.4
wt% Co). Bulk
composition (R. Korotev, WUSL)
INAA of subsamples gave mean abundances of (in wt.%) FeO 2.9, Na2O
0.69, CaO 16, (in ppm) Sc 4.6, La 1.2, Sm 0.58, Eu 1.6, Yb 0.36, Th 0.08,
and 1.1 ppb Ir.
Lunar (feldspathic melt rock).
20.3 g of type material and one polished thin section are at UWB. The
remaining material is held by the anonymous finder.
Dhofar 733 and Dhofar 1766 are distinct in having concentrations of Na and
Eu about twice that typical of other feldspathic lunar meteorites as a
result of more albitic plagioclase. Because they are compositionally
similar to each other and were found in proximity to each other, I suspect
that they are paired despite the textural differences.
733 | 1766
Schematic Map of the Find Locations of the
Dhofar Lunar Meteorites
Demidova S. I., Nazarov M. A., Lorenz C. A., Kurat G., Brandstätter F.,
and Ntaflos Th. (2007) Chemical
composition of lunar meteorites and the lunar crust. Petrology 15 (4), 386-407.
Foreman A. B., Korotev R. L.,
Jolliff B. L., and Zeigler R. A. (2008) Petrography and geochemistry of Dhofar 733 - An
unusually sodic, feldspathic lunar meteorite. Lunar
and Planetary Science XXXIX, abstract no. 1853.
Y., Yamaguchi A., and Ebihara M. (2019) Geochemical
study of feldspathic lunar meteorites Dho 307,
309, 908 and Dho 733. 50th
Lunar and Planetary Science Conference,
abstract no. 2394.
Korochantseva E. V., Buikin
A. I., Hopp J., Korochantsev
A. V., and Trieloff M. (2016) 40Ar-39Ar
results of lunar meteorites Dhofar 025, 280, 309, 730, 733, 1436, 1442, SaU
449, NWA 6888. 79th Annual Meeting of the Meteoritical Society, abstract no. 6317.
Korotev R. L. (2005) Lunar geochemistry as told by lunar meteorites. Chemie der Erde 65, 297-346.
Korotev R. L. (2012) Lunar
meteorites from Oman. Meteoritics
& Planetary Science 47, 1365-1402.
Korotev R. L. (2017) Update
(2012–2017) on lunar meteorites from Oman. Meteoritics & Planetary Science
Korotev data on Omani lunar meteorites.
Korotev R. L. and Irving A. J.
(2014) Keeping up with the lunar meteorites - 2014. 45th Lunar and Planetary Science Conference,
abstract no. 1405.
Shukolyukov, Y. A., Nazarov,
M. A., Ott, U. (2004) Noble gases in new lunar meteorites from Oman:
Irradiation history, trapped gases, and cosmic-ray exposure and K-Ar ages. Geochemistry
International 42, 1001-1017.
Wittmann A., Korotev R. L.,
and Jolliff B. L. (2014) Third of a kind — Impact melted lunar granulitic
breccia meteorite Dhofar 1766. 45th Lunar and
Planetary Science Conference, abstract no. 1182.
Back to: Lunar Meteorites | List of Lunar Meteorites | Top of Page