Indochinite
Indochinite among the tektites , natural glasses that the impact of meteorites originated.
There are four major stray fields on earth where tektites are found: The largest, the Australasian field, includes Australia , the Philippines , Indonesia and parts of Indochina and China . The tektites found in the area of Indochina ( Vietnam , Cambodia , Laos ) are called Indochinites. The associated meteorite probably hit the Bolaven Plateau in Laos about 790,000 years ago, leaving an impact crater covered by volcanic basalt deposits .
The Indochinites, which are currently often offered - often incorrectly as meteorites - are mainly found in the Thai province of Khon Kaen northeast of Bangkok . Characteristic of the Indochinites from Thailand are the dark color as well as the deep melting holes and pits, similar to the regmaglypts that occur on iron meteorites . In terms of rock type, they are similar to earthly obsidian , but are very rich in silicate and almost free of water .
Chemical composition: 73% SiO 2 ; 12.8% Al 2 O 3 ; 2.4% K 2 O ; 4.4% FeO ; 2.5% MgO ; 1.0% CaO ; 1.5% Na 2 O 3 ; 0.7% TiO 2 ; 0.1% MnO ; 0.04% Fe 2 O 3