Should mars really be black? Astronomy Now article

[h4tt3n]

http://www.astronomynow.com/news/n0909/18mars/

 

“Subsequent analysis of the flask material and dust has shown that the magnetite was transformed into the red mineral hematite, through a completely mechanical process without the presence of water at any stage of this process.”

 

Can magnetite Fe3O4 really be transformed into hematite Fe2O3 through a purely mechanical process? Magnetite consists of a mixture of iron(II) and iron(III), and hematite is just iron(III), so somehow there's a room-temperature redox process going on?

 

Cheers,

Mike

[insane_alien]

i wouldn't have thought so since the iron/oxygen ratios are different and the fact that the oxidation of the iron changes REQUIRES there to be a chemical reaction.

 

some extra oxygen has to come from somewhere. it doesn't necessarily require the presence of water(the oxygen could come from atmospheric gases) but it definitely doesn't appear out of nowhere.

 

the article is scant on details and may be a misinterpretation of the papers conclusion(i do not have access to the paper in question) and if it isn't then the paper has made some elementary mistakes that'll be called out in peer review.