NWA 12691 — Quintessential Lunar Breccia

This is a cut section of a lunar meteorite (i.e., a piece of the Moon ejected off the lunar surface following an asteroid impact). 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. As one would expect, some of the Moon rocks returned to Earth by Apollo astronauts are exceedingly similar to lunar meteorites, and this is one such example.

The four cut faces of this meteorite reveal abundant anorthosite inclusions and other clasts of primarily olivine, pigeonite, augite and ilmenite suspended in a melt of dark charcoal-hued lunar regolith (lunar soil). The sienna hues seen are the result of the meteorite from which this specimen was cut having landed in the Sahara. The brecciated structure is the result of the crushing effect of multiple asteroid impacts on the lunar surface before one such impact ejected this material off of the Moon itself into space and then onwards to Earth.

NWA 12691 — the 12,691^st meteorite to be recovered, analyzed and published in the journal of record, the Meteoritical Bulletin — was classified by Dr. Anthony Irving, one of the world’s foremost classification experts of planetary material. With less than 1200 kilograms known to exist, the Moon is among the rarest substances on Earth; every single bit known is able to fit in the trunk space of a standard SUV. The portion recovered from Apollo Missions (382 kilograms) is untouchable to the public. As for the lunar meteorites, a good deal of that is also untouchable as a result of its residency in the world’s great museums. Cut on four sides, now offered is a splendid specimen of the Moon.

The official classification of this lunar meteorite appears in the 108^th edition of the Meteoritical Bulletin. A copy of the abstract accompanies this offering.