Mark with Japanese Mark: 大泉住人　幸翁 "Oizumi junin | #458188

大泉住人　幸翁 "Oizumi junin Sachio". This mark is from a tsuba and was made by Sachio, who worked as a sword engraver (soukenkinkou) in Dewa Province (present-day Yamagata Prefecture). Soukenkinkou is the Japanese name for metalworkers who design accessories for bladed weapons. A tsuba is a sword guard designed to protect the hand from contact with the blade. It also balances the weight of the sword.