A conical fragment of rock that is formed from the high pressure of volcanism or meteorite impact and has striations radiating from the apex.
A cone-shaped fragment of rock, probably formed by violent shock waves, as from meteoritic impact or atomic explosions.
A fractured, conical fragment of rock that has striations radiating outward from the apex. Shatter cones are believed to form when rocks are subjected to shock waves associated with a meteoric impact. They are typically between a few centimeters and a few meters long.