Don´t think so.
Just take a fast look in the book " the art of Japanese sword polishing" by Takaiwa Stetsuo, page 136.
"Water with cooper sulfate is applied to the ji wtih a Q -tip or Cotton wool while carefully avoiding wetting the hamon.
THE HAMON WILL FADE if the water and cooper sulfate reach it."
Well, I tried it out on a brocken blade without kissaki ...it is true. The hamon fades.
By the way : Ji-To means Stone for the ji, not ha. The ha is never polished by jito, only by variants of hato.
Greets
Stefan