NWA 1950

SNC Lherzolithic Peridotite

Two stones (414 and 383 g) were found in the Atlas mountains

(Morocco) in 2001 January and March. The exact location of find

is unknown. The meteorite is a cumulate peridotitic rock consisting

of olivine (~ 55 vol%), low and high-Ca pyroxenes (~ 35

vol%) and plagioclase glass (~ 8 vol%). Accessory minerals include

phosphates (merrillite), chromite and spinels (inclusions in

olivines and pyroxenes), sulfides (pyrrhotite), and a glass rich in

potassium.The igneous texture is very similar to that of the

ALHA77005. Classification and mineralogy (Ph. Gillet, ENSL,

J.A. Barrat, UAng, M. Bohn, Ifremer): pyroxenes are pigeonite,

En78Fs19Wo2-En60Fs26Wo14, and augite, En53Fs16Wo31-

En45Fs14Wo41; maskelynite ranges from An57Ab41Or1 to

An40Ab57Or3. The key element weight-ratios FeO*/MnO is close

to 30 for pigeonite and close to 50 for olivines. Geochemistry:

REE pattern similar to that of ALHA77005 but with higher values.

Specimens: type specimen, 20 g, ENSL; main mass, Fectay.