Hi,

I'm a geologist (igneous petrologist) and I'm totally baffled by the recent
microscopic images from Opportunity.

This is clearly a very fine grained chemical sediment with occasional
detrital grains (Blueberries). Its not detrital, not bedded.
Totally weird.
As for the "jointing" it almost looks like weathering along crystal
faces..but what.. calcite,dolomite, gypsum, barite????

What does the Mossbauer and Alpha Xrf say???? Oh to see the spectrums.

Certainly NOT volcanoclastic!

pj