Mark with Japanese Mark: 水戸住　美久 "Mito ju | #458298

水戸住　美久 "Mito ju Yoshihisa". This mark is from a tsuba and was made by Yoshihisa, who worked as a sword engraver (soukenkinkou) in Hitachi Province (present-day Ibaraki Prefecture) for the Tamakawa house. 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.