Yes, reinforced concrete is concrete but with iron/steel bars in it to make it stronger and able to be used for construction of large buildings etc. What your picture shows is probably a good example of where it is used.
Actually, there is something a little more fishy with these photos too - as well as what appears to be a piece of metal with a screw thread on it which is sticking out of that rock.
The "shadow" at the top appears to me to be very false as the other black "shadow" areas should be in sunlight if this is a shadow cast by the triangular rock. Finding the PDS version would be good so that we can verify the shadow aspect, and down the right side of the main central triangular rock in those two links posted above, there is a white zig-zag line edging to the rock. Now, I dont know whether this is due to the colour processing or whether it is there in the 'original' as far as 'originals' go.... It would not be there in real life so the detective work is finding out how it came to be in there and what other processing was done to the image.
This central rock is also quite interesting because the part which is blue/black on the right side at the base is actually not all of the rock and the rock itself extends further on right. The blue/black added part deceives the eye to imagining that the rock ends at the bottom right base where the blue/black ends. Zoom in and you will see this and that the rock itself at the right end tip (near to the end of the "metal rod") goes further off to the right and is a lighter colour which blends in with the surface colour. The black "shadow" underneath is also hiding something up there I believe.
I can see patterns in the sand with a track of doughnuts going off from the rock to a point about one sixth of the way along the top border and another coming from the left point of the rock going to the edge at 9 o'clock. I think this is another image which was maybe taken due to the rovers movement detection being triggered, but thats just a hunch and is going waaay too far out on a limb.
My database does not go down to Sol 63 for Spirit yet unfortunately.
If you have a look at Marsrocks post half way down this thread on fishes, you will see something which I think also looks like re-bar concrete reinforcing rods. It extends into the rock on the left.
I agree Xenon, this definitely needs more study! Could you folks take a look at the other images as well. The ones I have introduced in "can you please help me with the circled area." Thanks. I don't know what it is about it but just have a gut instinct kind of thing going.
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Live Hand In Hand And Together We'll Stand, On The Threshold Of A Dream
I have zoomed and adjusted the colour to show more detail, also there appears to be a figure carved on top of the rock, this is a very good find indeed and deserves more study.
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"Creating a fiction when stating a fact destroys the credibility of the truth one are trying to convey"
Ya know if you look at the pieces, especially the one in front of the your chosen piece, they appear that they are one in the same. The pieces in their group also look as if they all may be a part of a row and column.
Are these images anywhere near the image in the thread please can you help me with this red circled area?
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Live Hand In Hand And Together We'll Stand, On The Threshold Of A Dream
This looks rather like reinforced concrete to me. What do you think? The point is that it probably costs hundreds or thousands of dollars for each picture taken by the rover so they are not going to take a photograph unless there is something interesting in it. We just have to find it!