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RE: Khatryka Impact site
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A new meteorite find, named Khatyrka, was recovered from eastern Siberia as a result of a search for naturally occurring quasicrystals. The meteorite occurs as clastic grains within postglacial clay-rich layers along the banks of a small stream in the Koryak Mountains, Chukotka Autonomous Okrug of far eastern Russia. Some of the grains are clearly chondritic and contain Type IA porphyritic olivine chondrules enclosed in matrices that have the characteristic platy olivine texture, matrix olivine composition, and mineralogy (olivine, pentlandite, nickel-rich iron-nickel metal, nepheline, and calcic pyroxene [diopsidehedenbergite solid solution]) of oxidized-subgroup CV3 chondrites. A few grains are finegrained spinel-rich calcium-aluminum-rich inclusions with mineral oxygen isotopic compositions again typical of such objects in CV3 chondrites. The chondritic and CAI grains contain small fragments of metallic copper-aluminum-iron alloys that include the quasicrystalline phase icosahedrite. One grain is an achondritic intergrowth of Cu-Al metal alloys and forsteritic olivine diopsidic pyroxene, both of which have meteoritic (CV3-like) oxygen isotopic compositions. Finally, some grains consist almost entirely of metallic alloys of aluminum + copper iron. The Cu-Al-Fe metal alloys and the alloy-bearing achondrite clast are interpreted to be an accretionary component of what otherwise is a fairly normal CV3 (oxidized) chondrite. This association of CV3 chondritic grains with metallic copperaluminum alloys makes Khatyrka a unique meteorite, perhaps best described as a complex CV3 (ox) breccia.
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Khatyrka meteorite
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Third-ever natural quasicrystal found in Siberian Khatyrka meteorite

The first synthetic quasicrystal was grown in the lab in 1982, and there are now more than 100 types of lab-grown ones. But this is only the third type found in nature - all three from the Khatyrka meteorite from north-eastern Russia since 2009. The approximate composition of the first two had been created in a lab beforehand.
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When scientists traced a museum rock back to its origins, they uncovered mysteries about the early solar system.

One January afternoon five years ago, Princeton geologist Lincoln Hollister opened an email from a colleague he'd never met bearing the subject line, "Help! Help! Help!" Paul Steinhardt, a theoretical physicist and the director of Princeton's Centre for Theoretical Science, wrote that he had an extraordinary rock on his hands, one that he thought was natural but whose origin and formation he could not identify. Hollister had examined tons of obscure rocks over his five-decade career and agreed to take a look.
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Israeli Nobel laureate's crystals fell to earth in meteorites

The discovery of natural quasicrystals will be "a real shocker" for many geologists and those who synthesize them under laboratory conditions.
In 2009, Steinhardt and Luca Bindi at the University of Florence in Italy identified them in a tiny rock sample thought to be from the Koryak Mountains in the far east of Russia.
Tests on that only known natural sample suggested it came from a meteorite.

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Once Upon a Time in Kamchatka: The Search for Natural Quasicrystals

Over the course of the last year, through a remarkable investigation to be described elsewhere, we have traced the history to show that our sample was, in fact, originally attached to the holotype material; the rock was discovered by V.V. Kryachko in a blue-green claybed along the Listventovyi stream, off the Iomrautvaam tributary of the Khatryka River, a remote region in southeastern Chukotka. This locality in the Chetkinvaam tectonic mélange is a Triassic (about 200 million years old) ultramafic (silicon-poor) zone.
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The Discovery of the First Natural Quasicrystal

In 2011, a team of geologists from the Us, Italy, and Russia was organised to conduct an expedition to Chukotka to search the clay bed along the Listventovyi stream for more samples and to explore the structural geology of the region. the analysis of the 1.5 tons of material gathered there is not yet ready for publication, but it can be reported that new meteoritic grains have been discovered with icosahedrite and the other Cu-al metallic phases attached.
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See also Quasicrystal

Google earth file: Khatryka Impact site.kmz (1kb, kmz)

Latitude:62°39'11.36"N, Longitude: 174°30'1.54"E



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