I have this katana since 1994
From the begining it was not clear the sword maker of this katana since the ittosai yasutsuna i found was a Gunto sword maker and the mei is differnt from this since it has 6 kanjis compared with gunto maker that has 5.
This katana looks older than gunto swords
Also the steel and tempered looks complete different from Ittosai Yasutsuna Gunto swordmaker
If somebody could help me i would appreciate