History: Two pieces were purchased from nomads in Erfoud, Morocco, in October 2006 and
Physical characteristics: A. Habibi purchased two pieces with a total mass of 477 g in Rissani,
Morocco; several other pieces of the same stone totaling 895 g are with Ait Elkaid in Rissani,
Morocco. Dull black/brown fusion crust is nearly complete and inside slightly tarnished where
absent. It is a gray, coarse-grained, pristine magmatic rock consisting of millimeter-sized
phenocrysts of mainly pyroxene and plagioclase.
Petrography: (A. Jambon, O. Boudouma, and D. Badia, UPVI). The texture is best described
as shergottite-like. Pyroxene grains are highly fractured while plagioclase laths, partly
transformed to maskelynite, are only affected by a small number of fractures. Silica and
silica-feldspar glass are minor components. A few patches of impact melt are also observed.
Ilmenite, baddeleyite, zirconolite, tranquilityite, pyrrhotite, and metal. Fayalite associated with
silica probably results from the dissociation of iron rich pyroxene. Modal mineralogy (vol%):
Cpx 50, plagioclase + K-feldspar 32, silica + glass 7.5, opaques (ilmenite, Ti-magnetite,
pyrrhotite) + fayalite 7, voids + fractures 3.
Geochemistry: Mineralogy by EMP and SEM. (Trace and major element analyses ICP-MS and
ICP-AES, J.-A. Barrat, UBO). Pyroxene grains are complexly zoned (En65Fs21Wo13 to
En2Fs83Wo15; FeO/MnO = 78 [average]). A few compositions correspond to pyroxferroite.
Plagioclase is normally zoned from An75-91 (average An89) with minor olivine (Fa80-95).
Chondrite normalized REE pattern with an enrichment of 53 (La) to 40 (Yb). Trace element
pattern with negative anomalies of Sr and Eu. Interstitial glass is high in silica (75 wt%) and
contains microcrysts of K-feldspar with a significant celsian component. The chemistry and
major and trace elements are identical to NWA 032-479-773 and LAP
02205-02224-02226-02436- 03632. The texture is very similar to that of the LAP specimens.
The very low abundance of olivine and the relative abundance of silica in NWA 4734 are the
main differences beside the grain size and the slightly different composition of the major
Classification: Achondrite (lunar); extensive shock.
Type specimens: A total of 20 g of sample and one polished section is on deposit at UPVI.
Mbarek Ait Elkaid holds the main masses.
Image nwa 4734 1
Image nwa 4734 2
||Found 2001, Morocco
||double polished covered thin section