.55" Polished Rafsa 005 Angrite Meteorite Slice (0.67 g) - Algeria

Rafsa 005 is a rare kind of meteorite: it is an angrite, a class of achondrite that is the oldest volcanic rock known on Earth! These meteorites are basalts aged to about 4.5 billion years with unique oxygen isotope compositions that constrain their origins to the inner solar system. Their parent body was likely a destroyed parent body about the size of the planetoid 4-Vesta. Rafsa 005 is a plutonic variety of angrite, indicating it cooled slowly beneath its parent body's outer crust.

Rafsa 005 was found north of Tindouf, Algeria in 2023, and about 2 kilograms have been recovered. It was subsequently sold to collectors and disseminated onto the commercial market. It is characterized by calcium-rich pyroxenes with occasional diopside and anorthite. Polishing really does this meteorite justice: the interior is full of deep red-brown silicates and tiny mineral grains.

Achondrites are a type of stony meteorite that lacks chondrules--round grains that aggregate from molten or partially molten droplets in space to form chondrites. Achondrites still contain grains, but their textures are extremely distinct and analogous with igneous processes rather than the chondrule-producing conditions at the beginning of the solar system.

Achondrites make up about 8 percent of all known meteorites. They are almost all regolith breccias, ejected from impacts on larger asteroids and sometimes the moon and Mars. Most are HED (howardite-eucrite-diogenite) in composition, sourced from the asteroid Vesta: it is the second largest asteroid in the Solar System and the only asteroid visible to the naked eye.