Crossed-polarised images of set of five NWA meteorite thin section slides from Sahara (Morocco)

Set of five thin sections of NWA meteorites from the Sahara in Morocco.

These are from un-numbered meteorites and were sold as set of ebay by SDFossils in the UK. I do not know whether they are from different meteorites or five sections from the same meteorite. They are all show chrondules.

A meteorite is debris from space that survives impact with the ground.

NWA Meteorites: Northwest Africa (from https://en.wikipedia.org/wiki/Meteorite): Meteorite markets came into existence in the late 1990s, especially in Morocco. This trade was driven by Western commercialization and an increasing number of collectors. The meteorites were supplied by nomads and local people who combed the deserts looking for specimens to sell. Many thousands of meteorites have been distributed in this way, most of which lack any information about how, when, or where they were discovered. These are the so-called “Northwest Africa” meteorites. When they get classified, they are named “Northwest Africa” (abbreviated NWA) followed by a number. It is generally accepted that NWA meteorites originate in Morocco, Algeria, Western Sahara, Mali, and possibly even further afield. Nearly all of these meteorites leave Africa through Morocco. Scores of important meteorites, including Lunar and Martian ones, have been discovered and made available to science via this route. A few of the more notable meteorites recovered include Tissint and Northwest Africa 7034. Tissint was the first witnessed Martian meteorite fall in over fifty years; NWA 7034 is the oldest meteorite known to come from Mars, and is a unique water-bearing regolith breccia.

I don’t think my meteorite thin sections are not from Mars or the Moon! They are probably from a range of different unclassified meteorites – and this explains differences seen in the photos below.

It is quite possible that one or more of these thin sections come from “NWA meteorite 869”. The meteorite bulletin describes NWA 869 as follows at https://www.lpi.usra.edu/meteor/metbull.php?code=31890:

Northwest Africa 869

Northwest Africa

Find: 2000 or 2001

Ordinary chondrite (L4–6)

History: It is quite clear that meteorite collectors in Northwest Africa have discovered a large L chondrite strewn field at an undisclosed location. At least 2 metric tons of material comprising thousands of individuals has been sold under the name NWA 869 in the market places of Morocco and around the world. Individual masses are known to range from <1 g to >20 kg. It is certain that NWA 869 is paired with other NWA meteorites, although no systematic survey has been done. It is also possible that some stones sold as NWA 869 are not part of the same fall, although dealers are confident that most of the known masses are sufficiently distinctive from other NWA meteorites in terms of surface and internal appearance that the error rate should be fairly low. Scientists are advised to confirm the classification of any specimens they obtain before publishing results under this name.

Petrography and Geochemistry: (A. Rubin, UCLA) A fragmental breccia of type 4–6 material; one thin section dominated by an L5 lithology gave olivine (Fa24.2).

Classification: Ordinary chondrite (L4–6); W 1, S3.

Specimens: A 189.3 g type specimen is on deposit at UCLA.

Andy

Below with x25 Leitz objective, crossed polarised filters, Zeiss IM microscope, Optovar x1.0 setting:

Below with x32 Zeiss LWD objective, crossed polarised filters, Zeiss IM microscope, Optovar x1.0 (1st) and x2.0 (2nd photo) setting:

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