Muong Nong are the largest tektites in the world !!!! It is believed that the body that formed them was a comet due to the water molecules they contain Tektites are the result of the fusion and crystallisation of terrestrial material due to the high temperatures and pressures that are sometimes generated upon the impact of a large meteorite on the Earth's surface. They were expelled into the atmosphere by a huge meteor impact, 700,000 years ago, in the Gulf of Tonkin (Vietnam). The pieces were found hundreds and thousands of miles from the impact They are becoming scarcer, particularly those of a considerable size, as the ones offered in this lot. If it is already difficult to find a meteorite, a tektite is much harder to find because this phenomenon does not always happen  At Expometeoritos, we take care of dissemination, talks, workshops, analysis, classification and exhibitions of meteorites. We are members of: .- IMCA (International Meteorite Collectors Association) #8187 .- Meteoritical Society .- American Meteor Society All our pieces are certified and, if the value of the piece is over €300, we also provide its chemical composition analysis, carried out in our facilities by X-ray spectrography.