Like planets, asteroids are rocky bodies. If they were massive enough during their formation, they melted and formed concentric layers. Some asteroids broke apart and fell to Earth : meteorites.
Meteorites are fragments of big asteroids, coming from the Asteroid belt between Mars and Jupiter. They have different structures, depending on where they come from.
On June 18, 1821, a meteorite of 91 kilos from the asteroid Vesta fell in the countryside of Juvinas, a small village in the Ardèche, north of Aubenas. The largest piece is kept at the National Museum of Natural History in Paris.