What is Yahazuba in Japanese Katana terminology?
Yahazuba is a type of irregular blade pattern (Hamon) (Midareba) in Japanese swords. The pattern resembles the part of an arrow called ""Yahazu"" that receives the bowstring, hence the name. Due to its distinctive shape, it is easy to identify when comparing with other blade pattern (Hamon)s.
Yahazuba is a blade pattern (Hamon) that occurs during the tempering process, depending on the temperature conditions. It is speculated that the pattern can become ""Hako Midareba"" or ""Yahazuba"" depending on the temperature.
Swordsmiths who have created Yahazuba include ""Hasebe Kunishige's"" son ""Hasebe Kunihei"" from the Koto period, and ""Shimada Yoshisuke"" who was active in Suruga Province (currently central Shizuoka Prefecture). In the Shinto period, there were swordsmiths such as ""Echizen Yasutsugu"" who was active from the late Sengoku period to the late Edo period, and ""Hizen Yoshifusa"" who was active in Hizen Province (currently Saga Prefecture and part of Nagasaki Prefecture).