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Philippinite
from the Bicol Peninsula of the Island of LUZON.
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.
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