Muonionalusta is an iron meteorite from Norbotten, Sweden. The first piece was found in 1906 by a 10-year-old boy tending cattle in the forest; meteorite hunters have recently returned to the site and have recovered numerous specimens. Many more pieces are probably buried deeply in the neighbouring bogs and swamps. The meteorite fell to Earth about one million years ago, possibly during a period when the region was glaciated; giving one of the highest terrestrial ages of any meteorite in museum collections. Despite its high terrestrial age, many specimens exhibit only minor weathering. The fine Widmanstätten pattern is quite apparent on polished and etched slabs of the meteorite as is the evidence in the kamacite structure (the low-nickel metallic mineral) for intense shock. This meteorite is a group-IVA iron derived from the crystallized core of a melted and differentiated asteroid. This asteroid broke up about 400 million years ago; the core shattered, sending Muonionalusta, Gibeon and a few dozen other IVA irons toward the Earth.

Muonionalustas are believed to be glacial erratics (material transported by a glacier) and their exposure to churning rocks and ice for tens of thousands of years explains the smooth surface and prosaic shapes of almost all specimens. As a result of being in one of Earth's largest rock tumblers, Muonionalusta meteorites were often rendered unsuitable for exhibit as sculptural forms, and instead were dissected to reveal their internal splendor in slices, spheres, watch faces and other jewelry.

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