"MarsFossils" wrote in message
m...
The image below shows either a fossilized root or an Opportunity
spherule with very distinct three part layering. Both are about 3 mm
in diameter.

http://aix1.uottawa.ca/~weinberg/mar...root_m_028.jpg

What do you think it is? It is the first spherule I have seen with
such a distinct core and layers.

Look also at my Mars fossils web page.

http://aix1.uottawa.ca/~weinberg/mars/

best,

Michael

It's just a weathered spherule (a concretion).