This page will give you some of the more technical Moldavite information.
Moldavite is a dull green or olive green tektite which most scientists agree was formed during a meteorite impact in the Nordlinger Reis Crater. This word comes from the Greek word tektos, which means ‘melted’; and was first employed by the geologist Franz Suess in the year 1900. Moldavites are not part of a meteor, their chemical composition fits to the first sedimentary layers in the mother crater. No typical elements known from meteorites are enriched in the Moldavite glass. Against many writers who like to sell Moldavites as meteorites, the facts show that it is a product of the fusion of a meteorite with the earth. Moldavite is one of the rarest materials on earth!
Some scientists used to consider tektites to be a special form of obsidian (volcanic glass). This opinion has been uprooted. According to Vladimir Bouška’s seminal work Moldavites: The Czech Tektites, Moldavites are more stable than terrestrial glass. Moldavites, like all tektites, contain far less alkali metals than common glass. As a result, Moldavites are much drier than terrestrial glasses, containing at least a hundred times less water than volcanic glass and five to ten times less water than the glass formed during nuclear blasts, which facilitates their easy differentiation from man-made colored glass materials. Moldavites have a melting point between 1100 to 1600 degrees Celsius. The time necessary for the hardening of the melt of tektites and obsidians was markedly different. Obsidians hardened much more slowly and their material structure displays signs of melt crystallization. This effect is not observed in tektites at all.
Czech Moldavites hold an especially significant position among other tektites. They are the only tektites that are transparent and that stand out with a variety of green shades. The application of Moldavites as precious stones started as early as the end of the 19th century. The unique jewels with cut Moldavites from that same time period have been preserved. The significance of Moldavites as precious stones has declined with time. A new wave of interest in Moldavites came about in the early 1980’s when a large number of new abundant deposits and occurrence sites were detected during extensive geological research. At present, several dozens of moldavite occurrences and accumulations are recorded that can be considered as deposits suitable for exploitation.