Indochinite Tektite from the Khorat Plateau, Thailand

We are offering selected spheres, drops and pancakes, most with interesting surface ornamentation. Tektites have been born when a big meteorite or comet impacted and and flung molten earthen material (with traces of the meteorite/comet) into space where it quickly cooled and rained back onto Earth. These tektites are potassium-argon dated to be about 780,000 years old. They have no crystal structure, similar to volcanic obsidian silica-rich glass (approx. 70-80% SiO2), and are, very approximately, similar to silica-rich igneous rocks (i.e. granite) in composition, but even more to some sedimentary impure sandstones like greywacke. Like meteorites they often show atmospheric melting and ablations as well as flight orientation. The return of rocks from the first manned mission to the Moon in July 1969 helped to provide conclusive evidence that tektites have not come from there.