NBC News — Russian researchers say they have found pieces of the meteorite that exploded above the Ural Mountains on friday. A total of 53 pieces were found near a frozen lake. The largest piece is a centimeter in diameter, and the smallest one measures about a millimeter.

Researchers have determined that the composition of the stones is typical of meteorites. More than a thousand people were injured last friday after a meteor streaked across the sky and exploded. The meteor is estimated to weigh about 10 tons.