Moldavite (Czech: vltavín) is a forest green, olive green or blue greenish vitreous silica projectile glass formed by a meteorite impact in southern Germany (Nördlinger Ries Crater) that occurred about 15 million years ago. It is a type of tektite and a gemstone.Material ejected from the impact crater includes moldavite, which was strewn across parts of Germany, the Czech Republic and Austria.
In 1900, Franz Eduard Suess pointed out that the gravel-size moldavites exhibited curious pittings and wrinkles on the surface, which could not be due to the action of water, but resembled the characteristic markings on many meteorites. He attributed the material to a cosmic origin and regarded moldavites as a special type of meteorite for which he proposed the name of tektite. Based on an analysis of 23 Bohemian and Moravian samples, in 1966 it was theorised that variations in their composition derived from fractional volatilization, and were not similar in origin to sedimentary or igneous rocks. Values were reported for a range of attributes: oxides, and densities and refractive values index. In 1987 it was recognised that moldavites were created following meteor impact which melted material and launched it into the air. As the material was airborne, it cooled and solidified. However, the plasma-like vapor at the impact site separated primary melt droplets from other residual vapour. The former then cooled into moldavite. In 2019 the first LIBS (Laser Induced Breakdown Spectroscopy) study on two typical moldavite samples, followed by routine EPMA (Electron Probe Microanalysis), indicated agreement with EPMA studies and also revealed siderophile elements (Chromium, Iron, Cobalt and Nickel).
Moldavites' highly textured surfaces are now known to be the result of pervasive etching by naturally occurring CO2 and humic acids present in groundwater. Because of their extremely low water content and chemical composition, the current consensus among earth scientists is that moldavites were formed about 14.7 million years ago during the impact of a giant meteorite in the present-day Nördlinger Ries crater. Currently, moldavites have been found in an area that includes southern Bohemia, western Moravia, the Cheb Basin (northwest Bohemia), Lusatia (Germany), and Waldviertel (Austria).[13] Isotope analysis of samples of moldavites have shown a beryllium-10 isotope composition similar to the composition of Australasian tektites (australites) and Ivory Coast tektites (ivorites).
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