Help! Pics Added Stain (I think) Advice Appreciated

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Hello All,

 

Long time....Back into the game again . Recently picked up a Wak had quesitons. I have two videos one shows the blade with no stain at all and other side with stains. (I think).  Under direct light the darker areas take on a slightly brownish/yellowish hue) They don't feel like scratches. If it’s a stain can it be removed with another product??  I tried 99 percent Isopropyl Alcohol and Choji Oil with no effect,  Any idea what these black marks are? 

 

 

 

Video One: 

 

Video Two

Best 

 

Steven

 

 

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Guess what is throwing me off is the black marks in the 2nd video.( the very end shows the black discolorations)

 

The hamon is white throughout until it reaches the two black stains pictured after which the hamon is white again.  This occurrence is also a repeated  a couple times elsewhere
 

 

 

 

 

 

 

[French nihonto]

It's really difficult to say. I have the impression that the steel has been heated with something. I hope it's not that because that would be irrecoverable.  
Or burnt by a chemical element 

[ROKUJURO]

Steven,

it is very difficult to photograph NIHONTO, even if you have some experience. But from your photos, I find it almost impossible to see anything. The first video is too fast, and the camera goes elsewhere, and the rest would have needed a dark room to avoid reflections.

 

What you might have there could also be streaks from the contact with the SAYA and nothing IN the steel.

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Thank you Maxime and Jean 

[2devnul]

Hello Steve,

 

I can see what you refer to and what concerns you. I've seen similar 'stains' in past. 

Here is an example:

https://www.e-sword....isashi/2310-2011.htm

 

Maybe it is Hadori flaw, maybe just old-oil cover (should be easily cleaned), hard to tell from pictures. If it is heating problem (as mentioned by Maxine) then it is bad. I think that only experienced Togishi could tell you more about it and if it can be removed/fixed.