I was thinking that my recent Coal Script photo might be interesting with some sort of background layer, and remembered this old coal mine image. It's from early 1978, taken on a backpacking trip to eastern Ohio.
I wasn't able to come up with anything I liked as a composite with the coin, but I'm, pleased with this rendering of the original photo.
The original is an Ektachrome slide from my original (film) Canon TX camera. There's quite a bit of digital darkroom added here.