However, new analysis of spacecraft observations in combination with novel laboratory techniques shows that Mars’s red colour is better matched by iron oxides containing water, known as ferrihydrite. Ferrihydrite typically forms quickly in the presence of cool water, and so must have formed when Mars still had water on its surface.
My completely unfounded theory is Mars’ iron core was puked out all over the ground and the water rusted it away. That turned her red and lost her magnetosphere.
Mars’s iron content is not that far off from the Earth’s mantle. The name for this type of rock on Earth is “mafic”, because of the magnesium and ferrous (iron) content.
On Earth, the processing of plate tectonics selects for iron-poor rocks within continental crust in favour of felsic (feldspars) silicates with a lower melting temperature.
Mars has no plate tectonics and therefore has a more primordial mafic composition.
Puked out, like from volcanic eruptions?
Yea. I have no idea if there is evidence of that or not. I never really studied Mars more than, “red planet.”