QUESTION:
If Mars is essentially a rusted planet, would it be possible to release the
oxygen stored in the rust to provide the planet with a breathable
atmosphere, or use it to sustain a permanent base on the planet's surface? 
Have any calculations been made to determine the amount of oxygen stored in
the martian rock and/or soil?

ANSWER from Ted Roush on July 16, 1997:
Given enough energy, always an expensive resource to produce, oxygen could
be released from the Martian materials.  Keeping it in the atmosphere might
be difficult as the oxygen would likely react with any freshly exposed
materials on Mars' surface.  I'm not aware of any specific calculations
being performed but you might read Resources of Near-Earth Space, J. Lewis
et al. editors, University of Arizona Press.