LL Group
This group represents the least common class of ordinary chondrites since it includes just about 1,100 members (again, including probable pairings). The "LL" stands for "low iron" and "low metal" reflecting that LL chondrites usually contain a weight percentage of 19 to 22% total iron, but only 1 to 3% free metal. Hence, they are only weakly attracted to a magnet.
Like the other ordinary chondrites, the LL chondrites show petrologic types from 1 - 7, but the distribution of types shows no distinct peak. The most common LL chondrites are LL6 and LL5 with about 400 members each. More unequilibrated types such as LL4 and LL3 are much more rare with just about 70 members each. The olivine in LL chondrites is more iron-rich than in the other ordinary chondrites, and this implies that the LL chondrites must have formed under more oxidizing conditions than the H or L chondrites. Older literature lists the LL chondrites often as "amphoterites" since they were thought to be a connecting link between chondrites and achondrites, but this name is misleading and no longer in use.
Scientists are still searching for a probable parent body for the LL group. One small main belt
asteroid, 3628 Boznemcová, has been spotted which exhibits a similar reflectance spectrum to the spectra of the LL chondrites, but with a diameter of just 7 km it seems to be too small to be regarded as the original parent body of the LL
members. Maybe it's just a fragment of a common ancestor which links the LL chondrites to 3628
Boznemcová, and further research will still have to find the real source of the LL chondrites within the dense population of NEOs crossing Earth's
orbit.
Bensour
Fall 2002, 12 february 16 h 17
LL6 Micro Breccia
TKW : around 45 kg recovered, Morocco
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Bensour -04
crusted fragment with velvet crust
44gr
Price
on request
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Bensour -05
crusted end cut with two cuts, nice visible
micro breccia
30gr
Price
on request
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Bensour -06
perfect crusted individual with velvet crust
37gr
Price
on request
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Bensour -07
100% crusted individual with velvet crust
30.5gr
SOLD
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Bensour -08
100% crusted individual with velvet crust
15.82gr
SOLD |
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Bensour -09
98% crusted individual with velvet crust
10.06gr
Price
on request
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Bensour -10
97% crusted individual with velvet crust
9.70gr
Price
on request |
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Bensour -11
crusted individual with velvet crust, has
secondary crust
8.42gr
Price
on request
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Bensour -12
flat crusted individual with crust
3.81gr
SOLD |
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Bensour -13
crusted individual with velvet crust
7.49gr
SOLD
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Bensour -14
perfect crusted individual with velvet crust
7.55gr
Price
on request |
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Bensour -15
Complete slice with fresh crust all around !
36.45 gr
Price
on request
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