Mark with Japanese Mark: 水戸住　美久 "Mito ju | #458299

水戸住　美久 "Mito ju Yoshihisa". This mark is from a fuchi 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 fuchi is a ferrule that is placed between the tsuba and a sword's hilt.