Porcelain is amazing stuff. But let me tell you which part of that video I found the most interesting. At the beginning it shows a guy making a
fire inside the mine. That's how hard rock mining, including hard rock mining for gold, was done before explosives. They would build a fire next to
a rock and then dump cold water on it. The sudden temperature change fractures the rock, and then they break it up, pull it out, and repeat the process again and again.