is a very rare ultramafic extrusive igneous rock, only formed from
extremely hot magma. These hot
lava flows may rapidly cool, resulting in a characteristic "spinifex" texture of
The source lava is so hot that the lava is thin, almost watery in
consistency. Conditions for the formation of this lava only existed when the
Earth was much younger and hotter, so komatiite formations are at least two
billion years old.