What is the definition of igneous? 1) A usually black or banded, hard volcanic glass that displays shiny, curved surfaces when fractured and is formed by rapid cooling of lava 2) A type of sedimentary rock formed from the accumulation of organic materials 3) A type of metamorphic rock formed from the recrystallization of existing rock under high pressure and temperature 4) A type of rock formed from the solidification of molten material