Metal Embossing Plates

While searching for wire I came across my book of embossing plates (stencils)  (they have been lying in a box for 7 years with the wire and a few other things I forgot I had -(a lot of stencil making materials )  - I am organized - I just cant remember where I put them -    these are typically for embossing paper but wondered if I could use them to emboss copper -  since they are as thick as paper I should be able to roll them through the rolling mill just like the paper patterns - I have yet to come across pics on the internet of them in use that way - but then  I havn't googled much on it as yet . When I shop I come across these every once in a while on sale and grab them - and I found that one of those dollar store photo albums holds them quite well - since its so cold it may have to wait til spring - but I put the book of embossing plates somewhere I would find them when I want them this time