Mars Rock – Martian Meteorite Sahara Desert, Mali, North West Africa

This somewhat rhombus-shaped complete slice is delimited by the meteorite’s exterior rim gilded with a desert varnish, the result of prolonged exposure to Earth’s desert elements. On the cut surface, green-orange olivine phenocrysts are set in a groundmass of white plagioclase and light green pyroxene. Fine, dark, shock-melt veins course throughout the specimen. This is a complete slice of a Martian rock that is so exotic, it does not fit into any of the standard subtypes under which Martian specimens are normally designated. Modern cutting.
102 x 59 x 2 mm. (4 x 2.33 x 0.1 in.)

23.2 g.

This is a unique sample of the planet Mars. As is the case with the Moon, specimens of the planet Mars are among the most exotic substances on Earth with less than 180 kg. known to exist. The delivery mechanism to Earth was an asteroid impact on Mars that ejected material off the surface into interplanetary space; some fragments were eventually nudged into an Earth-crossing orbit. The determination of Martian origin is the result of research conducted by hundreds of scientists throughout the world. In addition to many arcane chemical and isotopic markers, most Martian meteorites have an unusually young crystalline age.

This particular Martian sample is unlike any other rock from Mars. Martian origin was determined by its oxygen isotopes, the ratio of iron and manganese in its clinopyroxene and olivine and the anorthite content of its plagioclase. Whereas most of the plagioclase in typical martian basalts has been transformed into maskelynite (impact glass formed during launch), only about 10% of the plagioclase in NWA 10416 has been transformed. This may indicate that this meteorite was launched off Mars by a rare oblique impact event. In effect, NWA 10416 is a great rarity: largely unadulterated Martian basalt. The author of the scientific abstract on NWA 10416 is Dr. Carl Agee, among the world’s foremost classifiers of Martian meteorites, also the lead investigator of another famously exotic Martian meteorite “Black Beauty”. The official classification of this meteorite appears in the 104th edition of the Meteoritical Bulletin. This is a limited offering intended for the most discriminating of collectors. The vast majority of NWA 10416 is being distributed among the world’s great research centers.

The main mass from which this slice was cut will be on display at the Maine Mineral & Gem Museum.

Christie's would like to thank Dr. Alan E. Rubin at the Institute of Geophysics and Planetary Physics, University of California, Los Angeles for his assistance in preparing this catalogue note.