Similarities & Differences -
L3 & LL3 Chondrites
When studying NWA 3099 (L/LL3)
it is evident that there are numerous unusual inclusions within
the matrix.
When comparing this meteorite with NWA 864 (L3.3) there are
notably similar inclusions present. These are the mottled
greyish inclusions which contain much smaller (~0.1-0.2mm) paler
inclusions inside. I have discussed this with fellow collector,
Bernd Pauli who came up with some very interesting theories.
This is what Bernd had to say about NWA 3099:
"While rare; it may be possible that this
meteorite contains Carbonaceous inclusions. A well-known example
is Krymka (LL3.1/S3) some slices of which include black
carbonaceous material, referred to as 'Mysterite'.
Interestingly, where there is Mysterite in the Krymka chondrite,
there is also abundant Troilite (Iron Sulphide) in the matrix. There are also
graphite-bearing fragments and, again, these fragments contain a
high abundance of Troilite and graphite.
Maybe NWA 3099 is as, or, at least almost as "primitive" as
Krymka or even Semarkona and thus would contain material from the early
days of our solar system. Like in Krymka, the C-rich clasts might be of a
pre-accretionary nature, and maybe there are even presolar nanodiamonds like the
ones that have been reported from Krymka. Maybe there is even a relation
to cometary material as has been assumed for Krymka carbonaceous material."
Even though the overall matrix of NWA 3099 is reasonably pale in
colour, I have since found similar
mottled features in NWA 1933 (LL3) which has a much darker
appearance. Bernd also immediately
recognized the same dark matrix, many crisp chondrules and
inclusions of NWA 864 (L3.3) as is evident in Krymka (LL3.1). On
further checking, the Meteoritical Bulletin actually makes
special note that NWA 864 is Highly Unequilibrated and thus
probably has a petrologic grade lower than the official level of
L3.3. It also says that its matrix contains fine blades and
laths of Iron rich olivine and is very similar to the Krymka
(LL3.1) matrix.
When viewing these different Type-3 Chondrites, it seems
relatively comprehensible to assume that there may indeed be one
common source (parent
body) or a number of related sources in which
these incredible primordial meteorites originated.
Mottled Grey /
White Inclusion in NWA 3099.
NWA 3099
(L/LL3) - 11.80g Complete Slice.
NWA 1933
(LL3) - 7.60g Complete Slice.
NWA 864
(L3.3) - 7.60g Endcut.
Krymka (LL3.1) - 6.80g Complete Slice. (Bernd Pauli Collection)
Krymka
(LL3.1) - 5.58g Complete Slice. (Peter Marmet Collection)
Dho 008
(L3.2-3.3) - 2.20g Partslice.
Sahara 98175
(LL3.5) - 3.94g Endcut.
Moorabie
(L3.8) - 0.256g Partslice.
NWA
2288
(L3) - 9.41g Slice.
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