Moldavite Bohemia (2) Meteorites Raw Minerals Stones Rocks Collecting

Description

Origin : Bohemia (Czech Republic)

Geological era : Miocene

Age : 15 million of years

Size : 4.5 k - mm 11 x 10 x 6

Rare fragment of meteoric origin Moldavite 4.5 carats - mm 11 x 10 x 6 Meteorites Tektites Raw Minerals Stones Rocks for Collection, in plexiglas box diam. cm 3, only a piece, as in photos.
Fall period: Miocene (14.5 million years).
Included to the Meteorite a geological tab dates paper.
Also available in lots, at this link.

Moldavite (in Czech: Vltavín) is a rocky projectile of greenish, olive-green or greenish-greenish silica formed by the impact of a meteorite in southern Germany (Nördlinger Ries Crater) which occurred in the Miocene around 15 million years ago. It is considered one of the four main species of known tektites.
Moldavite was presented to the scientific public for the first time in 1786 as "chrysolites" by Týn nad Vltavou at a conference by Josef Mayer of the University of Prague. Zippe (1836) used for the first time the term "Moldavite", derived from the Moldau river (Vltava) in Bohemia (Czech Republic), from where the first pieces described, originally considered as an artificial product, came from. Later it was thought to be a variety of obsidian, but the high melting point and its chemical composition excluded the hypothesis of volcanic origin. Moreover, the nodules and the curious pitting and wrinkling on the surface, can not be due to the action of water, but they resembled the characteristic signs of many meteorites. In 1900, F. E. Suess pointed out that the Moldavites showed curious wrinkles on the surface. He attributed the material to a cosmic origin and considered the Moldavites as a special type of meteorite for which he proposed the name of tektite.
Because of their difficult fusion, extremely low water content and chemical composition, the current opinion among scientists is that Moldavites formed about 14.7 million years ago during the Miocene, following the impact of a gigantic meteorite in the current crater Nördlinger Ries. The splashes of molten material as a result of the impact cooled while they were in the atmosphere and most fell into Bohemia. Moldavites have now been found in an area including Southern Bohemia, Western Moravia, the Cheb Basin (Northwestern Bohemia), Lusatia (Germany) and Waldviertel (Austria), widely distributed in deposits of clays and gravelly river sands. The isotopic analysis of Moldavite samples showed an isotopic composition of beryllium-10 similar to the composition of the Australian-Australian tektites and the Ivory Coast (ivorites).
Ninety-nine percent of all Moldavite findings come from Southern Bohemia, while one percent of them were found in southern Moravia. Only a few dozen pieces were found in the Lusatia area (near Dresden), in the area of ​​the Cheb basin (western Bohemia) and in northern Austria (near Radessen).
The color of the Moldavites of Moravia usually differs from the Bohemian counterpart, as it tends to be brownish.
The total amount of Moldavite spread around the world is estimated at 275 tons. Currently there are only four Moldavite active mines in the Czech Republic. It is expected that in less than ten years they will be exhausted, without any appreciable quantity of Moldavite left in the ground.
Much appreciated by connoisseurs, it is often used in craft jewelry, cut and polished as an ornamental stone under the name pseudo-chrysolite. Also used in crystallotherapy, as such it has acquired an almost cult status.