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22.1 grams. CR-an
TKW 115 kg. Fall not observed. Found 14 February 2000, in the Tenere desert, Niger.
From the MetBul:
The dominant lithology has a coarse grain size. It consists of olivine (poikilitically enclosed within pyroxenes in the relic chondrules), a small amount of plagioclase, 10% metal in rounded or oval-shaped grains often edged by chromite, and minor sulphides in small grains. The interchondrule matrix consists of subhedral crystals of olivine embedded in plagioclase and within anhedral crystals of chromite and phosphate that are up to 1 mm in size. Two distinct plagioclase compositions are present: An46.4Or2.2 in the matrix and An26.6Or5.2 in chondrule relics. A second lithology is finer grained and porous, without large metal grains but with fairly abundant sulphide grains.
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Found at the arrow (green or red) on the map below
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Andreas Ruh 6/6/2019 5:27:13 AM |
Hello Anne,
this classification is not up-to-date. There was a reclassification in 2017 (see MB 105). Based on a publication from 2012 (Gardner-Vandy et al., GCA 85, pages 142-159, 2012), this correction was necessary. As a result of this study a relationship with the CR chondrite parent body was ruled out. Tafassasset was classified as a primitive achondrite similar to LEW 88763 and Divnoe. |
Paul Swartz 6/4/2019 10:00:31 PM |
Aye! 2000 it is. |
Anne Black 6/4/2019 2:14:00 PM |
Yes, John, there has been a lot of questions about this meteorite and its pairings, so a few years ago Alain Carion and I asked Drs. Ted Bunch and Tony Irving to look at it and we supplied them with a large slice. Their answer was that it originally was a carbonaceous CR6 that later went through a metamorphic phase, so it is a Meta-CR6. And Dr. Bunch published the whole study and explanation on NAU's website. (I'll have to look for the exact link). And they insisted that it never was a primitive Achondrite. |
John Divelbiss 6/4/2019 11:30:20 AM |
found in 2000, not 2011 as noted above...Tafassasset, is it fully equilibrated or is it a primitive achondrite??? That was the big question, even in 2002 when I bought my first piece, a 1.2 g slice, from Alain Carion at the Springfield show that summer. I know he was CR all the way. I said it is primitive either way. :) I later bought other pieces from Anne and Fabien. |
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