This is a lunar meteorite — that is to say, a piece of the Moon ejected from the lunar surface following an asteroid impact — that was cut and polished to reveal its matrix. The analysis of a researcher to confirm its lunar origin was vetted by a panel of colleagues prior to publication in the catalogue raisonnée of meteorites — the Meteoritical Bulletin. Lunar specimens are identified by specific geological, mineralogical, chemical and radiation signatures. Many of the common minerals found on Earth’s surface are rare on the Moon; in addition, lunar rocks contain gases originating from the solar wind with isotope ratios that are markedly different than the same gases found on Earth. Finally, lunar samples brought to Earth by the Apollo missions are closely similar to suspected lunar meteorites — and this is one such example. The Moon is among the rarest substances on Earth and now offered is a durable pocket-sized example. (For more on lunar meteorites and NWA 12691 in particular, see lots 6, 26, and 52).

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.

The analysis of this meteorite was led by Dr. Anthony Irving, whose findings underwent peer review by the Nomenclature Committee of the Meteoritical Society. The analysis and classification was published in the 108th edition of the Meteoritical Bulletin — the official registry of meteorites.

32 x 43 x 10mm (1.25 x 1.66 x 0.33 in) and 23.54g (117 carats)