More psycho babble; "Today, the Martian surface is cold and dry,"... Today, the Martian surface is cold and dry, ...Today, the Martian surface is cold and dry, ... Today, the Martian surface is cold and dry,.

Odyssey has located hematite as well as olivine by way of the inferred camera. One canceling out the other perhaps for the understanding the history of water on Mars. Which for right now still leaves use with room for speculation, ah yes, good old mister speculation ;-)
Speculation with the possibility of a Mars picture that shows the color of green. Like the one in the link you posted Marcia. I don't find it unusual that a Mars picture would show some green, maybe refreshed by seeing one. The speculation part is, what is it? What would the green be, if you were to look at a photo with green in it? What shape and form would it come in if it was olivine? What if the green was not in that shape and form?

Woodlock