Tektites from the world largest Tektite strewn field with 10 mm rotatatation depression. Unsusal shape, one side is a disc, the back-side is a elongated triangular exaltation. Impressive dimension, with rotatation schlieren ; unfortunately with some bigger chips . Found in Guangdong province / China. Tektites are natural glass, generated by a huge meteorite impact. By hitting the ground the kinetic energy from the meteorite was set free in a huge explosion, that vaporised the meteorite and the surrounding earth surface. Jets of rock steam were ejected from the new born crater. The steam jets cooled down in the higher atmosphere and condensed to glass that rained down up to hundreds of kilometres away from the impact. 428g 96 x 80 x 47 mm scale-cube is 1 x 1 x 1 cm International meteorite collector association member number #3503