Maskelynite

Maskelynit is a diaplectic glass with the composition of Bytownite from which it is produced by shock events ( collisions, impact ) ( Impaktmetamorphose ).

Under the polarizing microscope Maskelynit appears due to its amorphous structure with parallel polarizers white and black with crossed polarizers. Despite the amorphous structure is considered maskelynite variety of Bytownite because it maintains the crystalline form of the feldspar, and non-melt flow, such as other Impaktgläser.

It was named after the British mineralogist Mervyn Herbert Nevil Story Maskelyne ( Astronomer Royal Nevil Maskelyne grandson ). Story Maskelyne was 1857-1880 Keeper of Minerals at the British Museum, and has glassy feldspar described as one of the first in meteorites.

Maskelynit found in meteorites, often in the shock veins of chondrites, but also in moon rocks. Especially a lot containing shergottitischen Martian meteorites, in which all plagioclase has been converted into Maskelynit. This is due to the fact that Mars meteorite must be accelerated to the high escape velocity of Mars to escape its attractiveness can. For instance, the found in the Omani desert on June 17, 2000 15 g heavy Mars meteorite Dhofar 378 47% Maskelynit, so he must have been subjected to a severe shock event, when he was cut off from its parent body.

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