Mark with Japanese Mark: 一乗斎　弘寿 "Ichijousai | #458323

一乗斎　弘寿 "Ichijousai Hirotoshi". This mark is from a kozuka, which is the hilt of a small, secondary knife. It was made by Hirotoshi, who worked as a sword engraver (soukenkinkou) in Hitachi Province (present-day Ibaraki Prefecture). Soukenkinkou is the Japanese name for metalworkers who design accessories for bladed weapons.