1.75" Etched Saint-Aubin Iron Meteorite Slice (26.86 g) - France

The Saint-Aubin Meteorite

The Saint-Aubin meteorite is a 472-kilogram iron (IIIAB) meteorite that landed in Champagne, France roughly 55,000 years ago. Farmers found five pieces in 1968 as they plowed fields.

Saint-Aubin contains the minerals sarcopsite and graphtonite, two related iron-nickel phosphate minerals, as well as long crystals of schreibersite, an iron-nickel phosphide mineral. It was originally classified as "ungrouped", but more recent work has shown it is a high-nickel, high-gold, low-iridium member of the (IIIAB) group. It often contains well-defined Widmanstätten patterns, and sometimes contains shock features such as Neumann lines, a shock-hatched kamacite structure.

About Iron Meteorites

Iron type meteorites are composed primarily of iron and nickel, and are the remnants of differential cores torn apart at the beginning of the solar system. These metallic meteorites are often the easiest to identify after millions of years post-impact because they are quite different from terrestrial material, especially when it comes to their mass-to-surface area ratio. They are exceptionally heavy for their size since iron is a high-density metal: this is also why the Earth's core is nickel-iron. As planets form, the densest metals form gravitational centers, bringing more and more material into their gravitational pull. In the solar system's rocky planets, these dense materials are most often nickel and iron.

Most iron meteorites have distinctive, geometric patterns called Widmanstätten patterns, which become visible when the meteorite is cut and acid etched. These patterns are criss-crossing bands of the iron-nickel alloys kamacite and taenite that slowly crystalized as the core of the meteorites' parent bodies slowly cooled. Such large alloy crystallizations for mover millions of years and do not occur naturally on Earth, further proving that iron meteorites come from extraterrestrial bodies.