Lunar meteorite (feldspathic breccia)
Sahara Desert, North West Africa
NWA 12691 is a quintessential lunar breccia. Numerous fragments of different lunar materials were naturally 'cemented' together as a result of the pressure and heat from repeated impacts on the lunar surface—with one such impact sending the rock from which this sphere was made off into space. The prominent white clasts seen are anorthite, which is very rare on Earth but not on the Moon, which are suspended in dark lunar regolith (i.e., lunar soil comprised of pulverized rocks including some volcanic glass, which melted following an asteroid impact and subsequently hardened). Scientists are readily able to identify Moon rocks by analyzing a rock's texture, mineralogy, chemistry and isotopic signatures. As an added reference, this specimen is nearly identical to some of the material returned to Earth by Apollo astronauts.
While meteorites are exceptionally rare—the weight of every meteorite known is less than the world’s annual output of gold—lunar meteorites are far more rare still. They represent just 0.5% of all meteorites and weigh in-total about 800 kilograms—every bit of which would fit in the back of an SUV. A good deal of this material is untouchable as it’s in museums and research institutions. As it regards the 380 kilograms of material returned to Earth by the Apollo missions—every milligram of that material is untouchable. Further, the cutting, grinding and polishing which occurs in the sphere fabrication process results in a good deal of material loss.
30 mm in diameter and 41.16 grams.
A copy of the scientific analysis and classification of NWA 12691 accompanies this sample.
Provenance: The Stifler Collection of Meteorites.
