Roman Metal Armour-Polished or Dull?

[Magnus]

Well, part of the reason for taking Britain was to secure the tin mines in Cornwall. But even before then, tin was pretty readily available since it was needed for all the bronze cookware and other household implements of the time, not to mention helmets, armor, and other military gear (before brass became common). Matthew

So they had enough readily available that the majority of their armour could very well have been tinned, including helmets and seggies. Ok, that's what I basically wanted to know.