Rocks from the Moon are among the rarest substances on Earth, and now offered is a quadrilateral (or rhombus) sample cut from one such rock that was blasted off the lunar surface following an asteroid impact. There are less than 750 kg of lunar meteorites known to exist and a significant fraction is controlled by governmental institutions. Every lunar meteorite known would fit into five footlockers. While Apollo astronauts returned with 382 kilograms of Moon rocks, not one milligram of this material is available for private ownership. Moon rocks are identified by specific textural, mineralogical, chemical and isotopic signatures. Many of the common minerals found on Earth’s surface are rare on the Moon and some lunar minerals are unknown on Earth. In addition, Moon rocks contain gases captured from the solar wind with isotope ratios very different from the same gases found on Earth. NWA 5000 is the 5,000th rock recovered in the Northwest African grid of the Sahara Desert to be analyzed and classified, in 2007 when it was discovered it was the largest lunar meteorite known.

The cut face of this slice reveals a galaxy of inclusions and minerals in a fine grained matrix. The low average concentrations of FeO and Th indicate this sample originated in the feldspathic lunar highlands. Its primary minerals are olivine gabbro clasts consisting predominantly of coarse-grained calcic plagioclase, pigeonite, olivine with accessory merrillite, ilmenite, chromite, baddeleyite, rare zirconolite, a silica polymorph, K-feldspar, kamacite, and troilite. The result of the ongoing bombardment of the Moon’s surface by meteorite impacts prior to the collisionresponsible for launching this rock to Earth.

Christie's would like to thank Dr. Alan E. Rubin at the Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles for his assistance in preparing this catalogue.

193 x 178 x 6mm (7.75 x 7 x 0.25 in.) and 406g

Meteoritical Bulletin, no. 93, MAPS 43, 571-632 (2008)

Royal Ontario Museum, Toronto, December 2008 -April 2009.