Does anyone know of a good technique for making a b/w photo look like a gold coin? I'm using PS-7, but I've just bought CS. (Not installed yet, but I will install it if the job is easier in CS.)

The attached photo is a jpeg of the image I'm trying to use, along with a shot of a random coin, just to show the basic look I'm trying to create. In the PSD file, the b/w portrait is already cut out and ready for whatever filtering/manipulation is required.

I've seen one tutorial for using a displacement map for doing it, but the final result didn't look realistic enough.

Any help would be greatly appreciated. I'll do the work, I just need a little advice on how to go about it.