WWMeteorites hunting team
 The "Black Beauty" Meteorite

Martian basaltic breccia

Complete slices cutted from a 4.25g

individual of this meteorite...

Very thin (0.9mm)

Northwest Africa 7034 and pairings is a Martian meteorite believed to be the second oldest yet discovered. It is estimated to be two billion years old and contains the most water of any Martian meteorite found on earth ( 6000 parts per million extraterrestrial H2O released during stepped heating). Although it is from Mars it does not fit into any of the three SNC meteorite categories, and forms a new Martian meteorite group named "Martian (basaltic breccia)". Nicknamed "Black Beauty", it was purchased in Morocco and a slice of it was donated to the University of New Mexico by its American owner.

NWA 7034 is a volcanic breccia that has a porphyritic appearance, consisting of plagioclase (andesine) and pyroxene (pigeonite and augite) phenocrysts that are up to 5 mm in diameter set in a fine grained groundmass. Accessory minerals include chlorapatite, chromite, goethite, ilmenite, magnetite, maghemite, alkali feldspar and pyrite. There are even some clasts present that are made of quenched magma. The groundmass is made from fine grained plagioclase, pyroxene, different oxide minerals, and traces of iron sulfides. The whole rock chemistry revealed that NWA 7034 has the highest water content ever measured in a Martian meteorite. The water might be derived from oceans that used to exist on Mars, but were still present when the volcanic rock, that would eventually become the meteorite, was erupted.

With an age of 2.089 ± 0.081 Ga (billion years) it was formed just at the beginning of the Amazonian period of Mars. It is the second oldest Martian meteorite known. Bulk oxygen isotope values of Δ17O = 0.58 ± 0.05 per mil and a heat-released water oxygen isotope average value of Δ17O = 0.330 ± 0.011 per mil, suggesting the existence of multiple oxygen reservoirs on Mars.