Achondrites include meteorites from asteroids, Mars and the moon. They are igneous, meaning that at some point they melted into magma. When the magma cools and crystallises, it creates a concentric layered structure.
This process is known as igneous differentiation. The rocky planets of Mercury, Venus, Earth and Mars, have also been formed by igneous differentiation, giving them planetary crusts, mantles and cores. Achondrites can, therefore, tell us a lot about the internal structure and formation of the planets.
Stony Meteorites without chondrules. Scientists believe that some of these meteorites originated on the surface of the Moon or Mars. 7.8 percent of meteorite falls are achondrites.