Tamahagane is a millennia old tradition of using iron sands sintered together in a charcoal furnace made of clay called a Tatara. The furnace is only used once before it must be disassembled to retrieve this precious steel. Very few tatara exist to this day and a good majority of the steel they produce is reserved for traditional katana forging. What steel does make it into the kitchen knife market is only sold to master bladesmiths and is one of the rarest steels in the world. The sintering process is also very similar to modern powdered metallurgy; meaning that, whilst not stainless, this steel should outperform other Japanese high carbon steel.