There was a time not all that long ago wherein refinement seemed like it would always be the name of the game. A big part of the reason why that is the case has to do with the fact that supposed refined manners were used as an exclusionary tactic after the progress of the industrial revolution made it so that any regular person could end up becoming wealthy beyond their wildest dreams. This made old money people feel like their social status was in jeopardy, and that is when refinement became a quality to aspire to so that new money people looked and acted like their old money counterparts instead of trying to rock the boat.
This trend has more or less died out, and you can keep this at the forefront of your mind while designing Metal Business Cards as well. You see, refined business cards have a decent feel to them, but suffice it to say that they can also look rather stuffy in some way, shape or form. There is a lot that can be gained from going for a rougher look, one that would eschew the bleached whites of refinement in favor of the beige and brown look of natural paper.
Paper is not white in its organic form. Rather, it needs to be put through a ridiculous chemical process before it can become truly white as the winter snow. Organic paper looks slightly yellow, and using this color in your business cards can allow you to adapt to the changing eras that we are all involved in. Refinement is no longer a quality worth focusing on, and roughness has its own charm.