Wolfe Creek Shale Ball: Iron Oxide, from the Wolfe Creek meteorite impact crater in Western Australia, 356g, about 8 x 6 x 6 cm. [The Wolfe Creek meteorite crater is one of the most 'obvious' meteorite craters on Earth with an average diameter of 875m, first spotted in an aerial survey in 1947. It is estimated that the meteorite that formed it was about 15m in diameter and had a mass of 17,000 tonnes. Small numbers of iron meteorites have been found in the vicinity of the crater, as well as so-called shale balls, rounded objects made of iron oxide. Shale balls are created by the slow weathering of the exterior of a meteorite]