The geological boundary between Triassic and Permian strata coincides with the greatest life extinction in the Earth 's history . Although the cause of the extinction is still the subject of intense debates , recent discoveries in the P - T boundary layer of shocked quartz grains , fullerenes with the extraterrestrial noble gases , Fe metal nuggets , and chondritic meteorite fragments all point to a powerful collision of Earth with a celestial body in the late Permian . Here we report the discovery of magnetic Fe , Si , Al - rich impact spherules which accompany the chondritic meteorite fragments in some samples from the P - T boundary layer at Graphite Peak , Antarctica .