Perchlorates being a rich source of oxygen might explain Mars 'ruddy' color.
It would interesting to know if iron-rich Hematite was a common mineral
all over Mars aeons ago.
Since Hematite is NOT noted for being reddish, chemical exposure
and reaction to the oxygen in perchlorates may have chemically broken down
most of the original supply of Hematite on the martian surface,
oxidizing the iron in the mineral turning the iron into the familiar
rust-colored dust found on the martian surface today.