Some quick analysis:
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Not the cleanest, neatest abrasion, as we see from the broken outline from 10 to 12 o’clock, but at least this stuff didn’t fracture badly, like the one further downhill that we made just last week (#38), or two other ones we made on this side of the crater rim (#36 and #33). Surprisingly, we successfully sampled the latter two, so #39 may be a candidate for drilling as well.
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The target rock seems reasonably hard (note that the chisel marks - those lines radiating outward from the centre - are well-preserved and easily visible), which is not always the case: see #32, which crumbled into dust every time we tried to sample the stuff.
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Those small, dark grains (toward the edge, between 1 and 2 o’clock) - pretty interesting; nothing quite like them has been found in any other target we’ve abraded on the rim so far. As a (very) general rule, darker minerals are often igneous (volcanic). Not saying that’s the case here, but they sure stand out in this buff/tan-coloured material.
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This crater rim/hillside really is an amazing place. The other patches I’ve linked to were taken just hundreds of metres away. We’ve made about 8 of these abrasion patches now over this one stretch of crater rim (roughly half a kilometre long), and we’ve sampled multiple times, more than in any other section. The geologic diversity packed tightly together in adjacent layers - featuring stuff like crater impact debris beside solid but heavily soaked minerals - is seriously wild!
Very cool. That makes sense, the outer surface may be some mixture of particles from many places but the interior would give a better indication of what the composition is deeper into the crust. Are there instruments capable of determine the age of the samples?
Not onboard the rover, no - which is one of the reasons many hardcore types are obsessed with sample return, in spite of the cost and extreme technical difficulty.
A number of age estimates for stuff in this area (the Jezero crater itself, the old mudstone down in the river delta we sampled last year, and so on) put them at easily 3.5 billion years plus - possibly older. That means the samples Perseverance already has in hand could be just as old as, or even older than, the most ancient sedimentary rock we’ve found on Earth. I get chills thinking about it.