The majority of meteorite falls are stony meteorites consisting mainly of silicate minerals. There are two main types of stony meteorite. Chondrites have never significantly melted and have compositions similar to the sun and the solar system as a whole. Achondrites have melted and are similar to igneous rocks on Earth.
These include rocks from Mars and the moon as well as from melted asteroids. Achondrites have compositions different from the sun as they have been changed by melting and crystallisation. Both chondrites and achondrites are split into many sub-groups based on their compositions, minerals and structures.