Removal of orange discoloration on Kurouchi finish

[thp]

I have a Raquin, which developed some orange discoloration on kurouchi finish. I have tried to clean it with bicarb and oiled it thereafter. And it keeps coming back following any wash with water. Oiling kind of makes it less visible but it is again apparent when oil is removed. Can somebody tell me how to clean it and keep it clean without damaging the finish. Thanks a lot

 

[McMan]

picture?

 

[thp]

Pictures added. Thanks.

 

[McMan]

Looks pretty faint. If you scrub at it a little bit with a paper towel+warm water, does the paper towel have orange on it? If so, rust. If not, likely just reactive steel and brown-ish patina.
If rust, @Kippington reports that dunk in boiling water, dry, repeat, for a few cycles can get rid of rust. (I've never tried this though.)

 

[josemartinlopez]

Are you sure it's not just the reddish clay @bryan03 uses?

 

[user 29468]

It’s clay for sure .

 

[thp]

Thank you all for your help, especially reassuring was Bryan's input.