Hello! As a fun side project for a nice practice showcase, I am rebuilding an old build that I did since my skills have grown exponentially since the previous version. That build is the recreation of Isengard from The Lord of The Rings! 
Now, I have a little texture dilema that i’m hoping some of you can help me solve. First off, i’m using really black marble, which is not shinny enough, and also not rough enough. If you’ve seen the movies, you’d notice that the tower of orthanc is made of a rough and yet shiny marbley black rock. Slate is to flat of a black and not marbley enough, and marble is not shiny enough, and not shiney enough. I can’t find a happy medium. Ultimately, i’d go with marble over anything else, but its really dark in the game, and seems to absorb a lot of light, and in normal circumstances the inside should be lit up pretty well with the surface lights and other lights i have in the place, but the black really absorbs it all. Marble also doesnt really reflect anything.
I’ve tried some marble textures, which gererally add a bit more of a shine to it, but, for some reason they don’t look right. Any suggestions or thoughts? 
here is the link to the place so you can see for yourself