"虻の目" "Abunome"

What is Abunome in Japanese Katana terminology?

Abunome is a distinctive blade pattern (Hamon) seen in the "互の目乱刃" (Gunome Midareba) of Hizen swords. In this pattern, the heads of the irregular blades are deeply burned with a roundness, forming a spherical shape. Among these, two adjacent ones look like the eyes of a horsefly, hence the name "Horsefly's Eye" (虻の目). This pattern is unique and is a characteristic feature of Hizen swords.