Mercurys color is a dark gray, with a rocky surface that is covered with a thick layer of dust. The planets surface is thought to be made up of igneous silicate rocks and dust, which gives it its light gray color. When observed through a telescope, Mercury looks dark gray and pockmarked due to its high iron content and lack of atmosphere. This color comes from Mercurys molten surface that cooled and hardened billions of years ago after the formation of the Solar System. Therefore, Mercurys color is primarily a result of its composition and the way its surface reflects and absorbs sunlight.