An Article In Meteorite-Times Magazine
by Tom Phillips
Crystallized Crust Of NWA 960
Very Rare Anomalous Chondrite
This one requires home work! The March 2007 Micro Visions is on this meteorite. I didn't have a thick sample to polish and examine at the time I wrote that article so go to that article (The link is at the top of this page) to se the thin section shots. This batch is of a polished sample viewed at 700X in cross polarized reflected light.
The April 2007 Micro Visions was titled Crystals in the Crust. Yes, you need to go to that one to. That crystal structure in the crust was the only time I had seen it in hundreds and hundreds of meteorites I have examined. I was floored when I saw the same structure in the crust of NWA 960. The last three images are of the crust. Don't be to hard on the shots. I only had a couple mm of crust on my humble slice to work with but you can see the structure I am talking about and compare it to what is shown in the Micro Vision article.
Perhaps I am onto some thing interesting.
This description was written by Adam Hupe.
NWA 960 Very Rare Anomalous Chondrite
THE TOOTH STONE
NWA 960 (Provisional), an acutely rare and Anomalous Type 3, S1, W1-2, Fa9.3 Chondrite found in the Sahara desert in 2001. We nicknamed this meteorite "The Tooth Stone" because it was like pulling a tooth getting it classified, taking well over 5 years, the longest in our history. Every time we inquired about it over the years, we were told that it was escalated to the next level. The classification of this meteorite was no easy task with six heavyweight laboratories involved with bringing its classification to a conclusion. NASA, JSC, UC, UW, NAU and Carnegie Laboratories all contributed to the data and concluded that it is Anomalous, meaning it is like nothing they had ever seen or understood before. Although the D17O values are near those for H chondrites, the d18O values are much higher, and the mineralogy of this specimen is very different from that of H chondrites. An extreme oddity is that absolutely no metal was found in this meteorite, even at the microprobe level. A Total Known Weight (TKW) of 997 grams is recorded for exceptional find.
From a visual standpoint, this is a very pleasing looking chondrite with crisp wall-to-wall chondrules. There are so many multicolored chondrules that we don't think that there is any room left for a matrix. Maybe, you could call the inexplicable sparse black clasts the matrix but only a few were found. Anyway you look it; nothing like this has ever been encountered before. There is a lot of behind-the-scenes interest in this meteorite so you may wan to pick up a piece of "The Tooth Stone" while these large specimens are available. It is certainly priced very reasonably considering it is a one-of-a-kind and a lot of resources were put into it.
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