Sword Tang Translation

[Rjizzle10]

Hey, I was hoping someone could help translate the characters on this tang for me. 
 

thanks in advance 

[xiayang]

義定 = Yoshisada

 

昭和十八年四月 = April of Shōwa 18 (1943 CE)

 

This is Ishihara Yoshisada, a Seki-based smith, see here.

[Rjizzle10]

Thank you very much for the translation. How rough would you say this blade is?
 

It’s got a visible straight hamon but looks to have some lines on it from something.

 

[Rjizzle10]

[mecox]

RJ, as Jan noted smith is Yoshisada  from Gifu Prefecture:  “Yoshisada” (義定), real name Ishihara Jō´ichi (石原錠一), he was born in Meiji 32 (1899) August 16.  He registered early pre-war as a Seki tosho in Showa 14 (1939) October 25,  age 40, so presumably had some experience before then.  He was living at Seki-machi, Nagasumi-cho.  He is listed as a Rikugun Jumei Tosho.  The sword is dated as 昭和十八年四月   Shōwa 18 (1943) April.   His blades have both Seki and Sho stamps.  Any stamp on yours?  The marks along the blade look like scratches.....mostly one side.... is there anything stuck in the saya?  But often scratches are by post-war kids chopping and slashing trees etc.