Philippinite from the Bicol Peninsula of the Island of LUZON.
Dimensions: 47.6 x 44.5 x 38.7 mm max.
We are offering selected spheres and pancakes, most with interesting breadcrust ornamentation and grooved curved polygonal flakes, typical for tektites of this region. The grooves are caused by surface erosion from chemicals in the ground. Not all Philippinites have grooves. Some Philippino natives call them "Star Dung". 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 moreto 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.