A class of stony-iron meteorite, mostly composed of small olivine crystals but also schreibersite, troilite, chromite, pyroxenes and phosphates. Pallasites were once thought to originate at the core-mantle boundary of differentiated asteroids that were subsequently shattered through impact. An alternative recent hypothesis is that they are impact-generated mixtures of core and mantle materials.
Pallasite is named after German naturalist Peter Pallas who, in 1772, studied a specimen previously found near Krasnoyarsk, in the mountains of Siberia. This rock had a mass of 680kg (1,500lbs) and was dissimilar to all rock or ore found in this area. However its content of native metal was similar to other finds from completely different areas. As the large piece could not have been accidentally transported to the site upon which it was found, the pallasite was consequently used to demonstrate the reality of meteorite falls on the Earth, which were, in the 1790s, considered by most scientists as fairytales.