Has It Been In A Fire?

[Daso]

Hello All,  This is more of a general learning/curiosity question.  I happily purchased my first papered Katana from a reputable dealer and very happy I did.  I do regularly peruse Ebay out of curiosity and fun and seem to often notice that the tangs of many of the Ebay swords look like a mottled rusted metal, very different than mine.  I've attached a photo from a listing and the Mei on it doesn't matter, but rather the color and condition.  Is this indicative of a blade that's been in a fire or just poor condition rust?  Just part of my learning.  Any thoughts would be appreciated.  I am not looking to purchase this sword at all, but it helps to understand signs of a sword that has likely been re-tempered or repaired from fire damage.  In the end, if you did find a good sword on the lark, does a re-temper lower its value, could it ever get papers? Thanks,

Darius

[Fuuten]

Blades that have been in fire, lose their tempering work. Those blades have been tempered during history, but i think having one re-tempered now won't be very good in a financial way. Lastly i think blades that have been tempered partly or whole in the past can receive papers.

[Daso]

Fuuten, thanks. I would never re temper a sword myself, I was more interested in how the tang looks on a blade that might have been in a fire and retempered

[Ken-Hawaii]

Looks okay to me, Darius. Fire damage would be a lot easier to spot on the nagasa, however....

 

Ken

 

[Daso]

Thanks. ken, I didn't know if that reddish rust on the tang gave away fire.

[Grey Doffin]

Evidence of retemper (most of which can be found on blades that haven't been retempered):

dry, parched feeling nakago, exaggerated curvature, weak, inconsistent hamon, mune-yaki, open, exploded grain, mizu-kage, and a hamon that begins above the machi.  With rare exceptions, retemper kills value.

Grey