Quoted from harryhoudini:
Here is a plastic test I did. Some spray paint and a piece of plastic. I think this could work well, I need to see if I have some blue in the shop but a combination of blue, black and gold probably makes a nice effect. This test is some gold on one part and then I flip it around and it's bronze with red sparkle mixed in.
This looks outstanding! Great job on the lighting. The plastic sheet does a really nice job for diffusion.