There are many ways of doing this effect, one way is to use a displacement map. The edges can be modeled as well. I whipped up a sample quarter that you can look at. The Texture maps come from https://www.usmint.gov/pressroom/index.cfm?action=photo#SQ2005
I can either email it to you, or post it on the forum after 5 my time. Figured that would be the easiest way of explaining it, sorry little time for a tutorial. But breaking the file apart should help figure it out. Hope that helps.
Nel Santiago
Broadcast Designer
KTVT CBS 11
Personal Site
https://www.ForbiddenSky.com