What?!?
There are no photosynthetic organisms on the surface of Mars. There are no lichens on the surface of Mars. Mr. Levin's remarks here border on the silly.
The colors of Mars we derived spacecraft imagery are just approximate visual interpretations of the actual data received. Getting more accurate in how we present this data isn't going to give us any better data to for "determining mineralogy."
Getting a more accurate color presentation of Mars is tantamount to adjusting the color knobs of your television set. You can improve the way the screen looks, but that doesn't improve the programming.