Armour is not a standard issue on Mars, but is also not uncommon. Armour built to withstand a properly-made ceramic slug would have to be extremely thick and heavy, and would render the wearer immobile. But short range fire is often with a cannister round. Add to this the danger from flying sabots, and it becomes apparent that a lighter form of armour will suffice for protection from a significant portion of musket fire.
Unsurprisingly, metal armour is too expensive (and probably too heavy) to be in common use. Most armour is therefore made from boiled, shaped leather or from laminated wooden strips. Both armours are usually coloured, often by dying (leather) or in the lacquering and sealing of the wooden strips. Shaped leather helmets are quite common, as are breastplates, vambraces and greaves. Armour is nevertheless often limited to officers and to royal troops due to its expense.