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310.7 grams.   L3.00

TKW 789 grams. Fall not observed. Found 2013.

Mendy writes:

The NWA desert continues to thrill us this with unique and amazing specimens. NWA 8276 is just such a meteorite. It is only the second L3.00 and is "possibly" paired to NWA 7731. NWA 8276 features a rich, black crust and a dark matrix densely packed with yellowish chondrules. As "extraordinary claims require extraordinary evidence", Dr. Carl Agee and Karen Ziegler did extensive and thorough research to support the 3.00 classification - a classification that indicates no heat or aqueous alteration of any kind (at least as far as can be presently evaluated). Though not listed as such in the MetBull entry, the shock is determined to be S2 or less as any shock level higher would create sufficient heat to alter the material into a higher subtype. The complete writeup for this classification may be found in the MetBul - click the meteorite classification above on this page.

The explanation how this meteorite was identified makes for a short but very good read (from MetBull):

Adam Bates identified this meteorite from images he received as a possible pairing to NWA 7731,even though they came from a different Moroccan meteorite dealer. Both pieces were then purchased within a few weeks of each other in October 2013.

Adam Bates and I partnered on half the stone and anxiously awaited for Dr. Agee's results. It was not a given that this was in fact paired with NWA 7731, especially since the meteorite was bought from a completely different dealer. There were visual differences between the samples that led Dr. Agee to initially believe that 8276 may be different from 7731. In the end, the classification came back as L3.00 but with enough differences to state that NWA 8276 is "possibly" paired with NWA 7731. The stone is quite fresh with a terrestrial weathering of W1.

Here is an edited excerpt from Dr. Agee's FB discussion with David Weir on the 3.00 classification and the rarity of this material:

Grossman and Brearley (2005)define the subtypes less than 3.2 as 3.15, 3.10, 3.05, and 3.00.This scale is primarily based on the mean value and standard deviation of Cr2O3 in coarse ferroan chondrule olivines. What will really improve the subtype 3 nomenclature (and understanding of unequilibrated OCs) are more samples like NWA 7731 and NWA 8276. Up to now we have so few in the 3.15-3.00 range that the statistics of small numbers makes it hard to have meaningful subdivisions. I would gladly use an even finer scale (i.e. 3.01, 3.02, 3.03, 3.04 etc.) if it were actually established. The Grossman and Brearley (2005) scale is the only one that presently exists with any sort of sampling to anchor it. There are just too few samples to establish a finer scale. The nice thing about discovering more of these very low type 3s is that more will hopefully be available for research. Semarkona, because much of it resides in India and some at the Smithsonian (I believe), it is hard to get a hold of. For example we only have a couple thin sections of Semarkona at UNM -- not even a tiny fragment!

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