0,55 gr Martian Meteorite NWA 15497, Shergottite

Rarity and Value
Martian meteorite NWA 15497 is an exceptionally rare basaltic shergottite originating from the surface of Mars. Formed through volcanic activity between 150 and 600 million years ago, this meteorite preserves direct geological evidence from the Martian crust. Its mineralogical composition, including maskelynite created by extreme shock pressure, together with pigeonite, augite, and olivine, records both volcanic and impact-related processes that occurred on Mars before the rock was ejected into space. Meteorites of confirmed Martian origin are among the rarest known extraterrestrial materials, making specimens such as NWA 15497 highly prized by collectors, museums, and planetary researchers.

Discovery
The specimen was recovered in 2020 in the Sahara Desert of Northwest Africa, one of the most important meteorite recovery regions in the world. The dry desert environment allows extraterrestrial material to remain preserved and distinguishable over long periods of time. Scientific examination confirmed the Martian origin of NWA 15497 through characteristic Fe/Mn ratios and trace element enrichment typical of Martian basaltic shergottites. These geochemical signatures provide important insight into volcanic activity, magmatic differentiation, and the internal evolution of the Martian mantle and crust.

Preservation
This slice preserves a fine-grained basaltic matrix composed of low-calcium and high-calcium pyroxenes, olivine, chromite, ilmenite, and sulfide minerals. The transformation of plagioclase into maskelynite records the immense pressures generated during the impact event responsible for launching the rock from Mars into interplanetary space. Minor secondary alteration minerals indicate limited terrestrial weathering after arrival on Earth. The specimen retains exceptional mineralogical integrity, preserving microscopic structures essential for scientific analysis and offering a remarkable physical connection to the geological history of another planet.

Composition

Maskelynite (shock-transformed plagioclase), low-Ca pyroxene (pigeonite), high-Ca pyroxene (augite), olivine, and accessory phases within a fine-grained basaltic matrix containing chromite, ilmenite, sulfides and minor secondary alteration minerals.

Geochemistry

Plagioclase (An35–55, maskelynite), olivine (Fa25–40), low-Ca pyroxene (En50–60 Fs30–40 Wo5–10), high-Ca pyroxene (Wo30–45), with Fe/Mn ratios consistent with Martian origin, and trace elements showing enrichment in incompatible elements typical of Martian basaltic shergottites.