I've came across a stunning piece of ,I think ,pure Black Marble,(it's from a Fire Display )and it's the long hearth section,It's about 5 feet x 2 feet,and the weight of it is serious,it's about 20 mm thick,I was thinking would it be possible,to cut and router a recess ,to catch a router plate?,if it can be done,is it with a special made router bit!.Where would I get such a bit,link provided if possible please,I will upload images later.