Nie/Nioi Structures

Yakiba/Ha Features and Terminology

Nie and Nioi are crystalline structures of martensite which are formed when the blade is quenched during the hardening process. Nioi is composed of very fine crystals and presents a misty appearance along the edge of the yakiba, delineating the hamon. Nie are coarser crystals which appear as bright spots or linear features on the blade surface. Often several of the structures shown here may occur on the same blade.

Ashi Ko Ashi Saka Ashi Choji Ashi Nezumi Ashi Uchinoke Yo Chikei

Utsuri Tobiyaki Muneyaki Kinsuji Inazuma Sunagashi Nijuba

Blade Characteristics Index and Site Guide