Sick love these, material looks great and the designs are sick too, whats your source? Ive been having a hard time finding good refs I like for metal and armour stuff with the right kind of shine too :3
I love doing metal surfaces, honestly I think they're are lighting at it's arguably simplist form. Highlight/midtone/core/reflective light. Atleast I think you don't have to be as subtle with them But then again I'm still learning!