Here is a card sculpture (actually, only a test sample) using a very nice metallic card stock I found. It's coated with a metallized mylar and it's really very convincing. I was thinking about making something like this; [link]
There are limitations to the material (cost being one of them) and the metallic coating needs to be peeled off any part that needs to be glued because the glue won't adhere to it. It also gets coated with fingerprints when handled (although I could wear rubber gloves when working with it).