What is Shihouzume of kanemasa

What is Shihouzume ?
shihouzuzme.jpgKATANA should have toughness to use as arms, in addition to the thin and graceful shape. KATANA has been evolved by pursuing toughness, strength, sharpness and beauty.
Shihouzume is the name of a manufacturing method of KATANA. Shihouzume are composed of the following four parts: Edge(刃鋼, Hakoh)to cut, Core(芯, Shin)to be flexible, Ridge(棟鋼, Munekoh)to be tough and Side(皮, Kawa)for beauty. The soft core is wrapped by Hakoh, Kawa and Munekoh to be forged into KATANA. Going through this process, the KATANA have both sharpness and strength in the graceful appearance that you have never seen

All of Kanemasa’s KATANA are made by the Shihouzume method, very sophisticated and reduced from many methods for making swords.