Crafty Mask Question

A friend has posed this query which I'm spreading further afield b'c I know I've got a whole mess of crafty-type folks on my FL who may have useful suggestions:

I have a mask, made of that plaster stuff, of my face. I would like to have a collage on the mask of some photographs. The pictures have been scanned, and I'm wondering, what would work best--printing on high quality paper, or photo paper, or? Any ideas?