The blade of the Japanese sword is made by heating the tamahagane (steel for making swords) to high temperature then hitting it flat with a mallet. They use a chisel to create the rift in the blades, fold it, then...
The katana Sadatoyo made looks amazing and is definitely worth the price. I am glad I chose him as the blacksmith, and will enjoy displaying and staring at this masterpiece for years to come.