I know you're reading this, Nick.
You're the professional geologist; I'm just a dillitente read up a little in that field.

Quite a proclamation, eh?
It's not my words.
Someone at JPL uttered those words more-or-less .

Check out this URL:
http://www.jpl.nasa.gov/mer2004/rover-images/jan-09-2004/images-1-9-04.html

Once there, check out the webpages for the spectral images produced by
Spirit's mini-TES on surface rocks bearing "bound water" [hydrates?]
and on the one captioned "rover senses carbonates". THEY FOUND THEM!!

It's interesting to speculate Nick if the hydrated martian-rocks detected
by mini-TES in Gusev Crater are either gypsum or zeolites.

As for the carbonates? THEY'RE THERE!!! Now precisely which rocks bear the carbonates?

Jacob

"To be courageous is not something one is endowed with by time, place or circumstances,
nor is it something that is acquired as a gift, a talent, nor learned or inherited. But every man will
have an opportunity in his life to show it."
PRESIDENT JOHN F. KENNEDY.