It’s all steel, I painted the plate armkr with a base coat of rustoleum hammer forged paint (mostly for rust prevention without needing to oil it) then I weathered it with accrylics. I darkened the hauberk by using bluing solution. I hand made the mail coif. There are some historical anachronisms, but I think they are reasonable.
Very happy with the way it looks.
You can! Just know it involves using hydrochloric acid. You do NOT want to breathe the resulting fumes. Wear a mask, rubber gloves, and goggles. You also want to check it in 10 minute intervals lest you just corrode the metal. Once it’s off you are left with just mild steel with no rust protection, so you have to use some kind of rust inhibitor. I looked up a video on youtube on how to “age” galvanized steel.
https://youtu.be/i6jBASEVsUM
Results may vary!