Muramasa Advice

[Valric]

Muramasa blades were banned on pain on death by the tokugawa shogunate. A lot of signatures were either erased or replaced in this time in order to hide the true maker of the blade. There aren't very many makers for which a fake signature is used to camouflage a higher quality blade from unwanted scrutiny... 

[SwordGuyJoe]

Muramasa is a different situation, since his blades were banned so many of examples were destroyed, mei removed, and in this case altered.

[Keiji]

This practice is called kaisan/kaizan (改鏨, lit. “change of chiselling´s”) or kaizan (改竄, lit. “to altger, to falsify, to fake”).

 

https://markussesko.com/2014/03/14/the-muramasa-ban-and-signature-alterations/

[Surfson]

So.....my original question stands.  By what criteria will the NBTHK let a sword pass with a false signature?  Is it only Muramasa?  Are there other swordsmiths whose swords were "camouflaged" for a similar reason?  Francesco's link takes you to Marku Sesko's piece that seems to indicate that it is generally allowed, but I'm wondering if there is a compendium of such swords for which Kaisan is allowed.  

 

[mywei]

Quite an interesting topic. Markus' article was very illuminating for me. 

 

It seems that not only signatures that were altered for 'superstitious' reasons i.e Shimosaka or Muramasa, but also ones altered for potential unscrupulous reasons i,e the Nengo date change from Tensho to Eisho are accepted by the NBTHK

 

Its not gimei as only a few of the characters in the mei have been altered

[Surfson]

Thanks for all of your input and advice guys.  I just bought it today.  Still in the bonding phase.... Cheers, Bob