The techniques developed in Seki, Japan over the past 780 years by their sword makers has established them as the best knife makers in the world. The fold, layer and forge method of making steel harder and stronger is the very essence of Seki's reputation. Kasumi has captured the spirit and technique of Seki's legendary sword makers. Kasumi uses V-Gold No 10 high carbon stainless. The blades are hardened to Rockwell C59 – 60 and therefore, keep a sharper cutting edge longer than any other knives. Both sides of the knife are clad with Damascus Steel. The KASUMI pattern that you see on both sides of the knives is the result of repeated folding and forging of the fine stainless steel into multiple layers.