"Greg Crinklaw" wrote in message
...
George wrote:
It's just a weathered spherule (a concretion).

Top or bottom. I don't think the bottom one is even a spherule. If you
look at the other images the matrix is full of these "blocky" structures
that are not apparently related to the spherules. The structures form a
sort of "braided" pattern, often concentric around a void. I think this
is just another example of one of those. Interesting, but not a
spherule cut in half as one might think at first glance.


Well, you've got me there. I didn't look at that second one, because,
unless I have a particular reason, I generally don't frequent an advertized
personal web site. The void to which you refer in the second image is
simplly that, a void left after a spherule was dislodged, that has become
weathered. In fact, I think a lot of the sructure that is shown is either
weathered molds for spherules, or voids for whatever minerals used to be in
the vugs but was weathered out (gypsum?).

--
Greg Crinklaw
Astronomical Software Developer
Cloudcroft, New Mexico, USA (33N, 106W, 2700m)

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