Tom Jacobs has recently released a new Substance Designer pack of a nice material with sharp rocks which can be found at train rails.
Always wanted to create these dense stones, that can be found mostly at train rails. I was focussing here on how to create a sense of depth and layered stones. The graph is available at Gumroad. The overall difference in height is also done within SD. So, there is no deformed plane.
100% substance designer and rendered in Marmoset.