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Dar al Gani 489
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SNC meteorites are pieces of Mars which were blown off the planet as a result of a large asteroid impact. When the Viking Probe landed on Mars and tested material on the surface, it verified this information. All of the SNCs are very rare and have always been VERY expensive. SNC: "Three types of achondrites are grouped together under the classification SNC. Each letter signifies the type of meteorite. The S stands for Shergottite, the name given the type of meteorite that fell in 1865 in the Indian State of Bihar, near the town of Shergotty. There are five known Shergottites. The N stands for Nakhlites, named for an achondrite that fell in Nakhla (near Alexandria), Egypt, in 1911. There are only 3 Nakhlites known. The C stands for a meteorite that fell in Chassigny, France, in 1815, called a Chassignite." Note: "If these rocks came from Mars, they would have carried traces of the Martian atmosphere. The noble gases Argon, Krypton, Xenon, and Neon have been detected in the Shergottites at levels that closely match the relative abundances in the Martian atmosphere, as found by the Viking Landers."
Information from the Meteoritical Bulletin:Dar al Gani 489...coordinates: ~27°08'N 16°05'E...Libya...Found 1997...Martian basalt (shergottite)...
A dark-brown stone of 2146 g was found in Dar al Gani. Mineralogy and classification
(L. Folco and B. Anselmi, MNA-SI): devoid of fusion crust; porphyritic basaltic texture
consisting of millimeter-sized phenocrysts of brown olivine (Fo61–78, Mn/Fe = 0.021–0.025
atomic) set in a more fine grained matrix of pigeonite laths (En57–72 Wo5–15,
Mn/Fe = 0.030–0.038 atomic) and interstitial feldspathic glass (An56–67Ab33–43);
minor mineral components include augite, chromite, Ti-rich chromite, ilmenite, merrillite
and pyrrhotite; texture, mineral modes and chemistry close to EETA79001 lithology A; shock
deformation features include twinning in pigeonite, strong mosaicism and planar deformation
features in olivine, and abundant impact-melt pockets and veinlets; pervasive veins filled
in by calcite are due to terrestrial weathering. Oxygen isotopes (A. S. Sexton and
I. A. Franchi, OU): d17O = 2.895, d18O = 4.980, and D17O = 0.305 permil. The petrography,
mineralogy, and noble gas chemistry of DaG 476 and DaG 489 are very similar, and the two
are likely paired (L. Folco, MNA-SI, and J. Zipfel and L. Schultz, MPI). Specimens: main
mass with anonymous finder, 34.9 g; two polished thin sections, MNA-SI
Some Facts and Information from: Rocks From Space second edition 1998 O. Richard Norton Mountain Press Publishing Company P.O.Box 2399, Missoula, Montana 59806 (406) 728-1900
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