This is a black-forged kitchen knife that inherits the tradition of Tosa sword smiths. It carries on a history of hundreds of years, and still maintains the hand-forging process. The material is high-grade steel, "Yasuki Steel Blue 2." Black-forged knives are also said to be resistant to rust. The sharpness is excellent and lasts a very long time. The sharpness can be maintained for a long time by sharpening. If you take good care of it, I think it will last a lifetime. I've been using this type of knife for many years. There's a quality you won't understand until you try it. Please be aware that it cannot cut ice.