This is the same slab of stone, ripped in half. So the left side is super hard and my grinder had a hard time cutting it down. The right side is super soft and I can scratch it with a wire brush. When I tried to thermal it, it wont spall, it just turns a deep pink and then black. The left side thermalled out perfectly. So I reground both sides to as flat as possible and used the heat to color them out about the same. The 50 grit dry polishing disc I have made the right side very clean, but won't pull the grind marks out of the left due to the hardness. It's as close as it's going to get. Still looks pretty good. Very interesting how the stone varies so much just from one side to the other of the same slab. Really threw me off when it wouldn't spall under heat. #valhalla#construction #idaho #design #designbuild #contractor #custom #homes #remodels #fireplace #stone #masonry #mantle #thermalling #cuttingtorch #spalling #spall #sandstone #slab #natural #wontspall #sunburn #pink #color #burnit #polish #smooth