Primitive Technology: Building furnace and casting knife copper beautiful

Hello. Building furnace and casting beautiful copper knife is our latest video. In this video we made a knife from the copper that we created. It took us a long time to collect the copper. We did a lot of experiments to melt copper to mold a copper knife, so many times we failed. We succeeded successfully and created a pretty sure and beautiful knife. Initially we collected the required amount of copper, we built a new oven with better wind system, we used coal ash to make a metal coke when melting. We use