How To Make Fake Rocks - swimmingpoolsteve
Fireplace Mantles - An artificial rock fireplace mantle is a slightly more advanced but extremely interesting artificial rock project that you could try. To make an artificial rock mantle / fireplace cover you would simply build a styrofoam core on a flat piece of plywood. The plywood should be 3/4" to 1" in thickness to prevent from sagging under the weight of the wet concrete you will apply.