Experiment of re-hardening
One of my friend found a "nice and doubtful" sword. It looks like a katana shortened from long tachi blade in 14th century. It looks very attractive. But the hamon was not very clear in that polishing. Then, he brought it to our office and study together.
Then, it turned out that it has no hamon. Actually, it has only some dim hamon in small part near the tang. And it disappears in most of upper part of the blade. We can find some hamon particles in some parts, though. Probably it was in fire in the past. The upper part was burnt out, and the tang part was left from the fire. We found such a blade sometimes. => A sword in fire accident
Of course, the white pattern on the blade is hadori what is created by polisher.
Blade length 64.6cm
It was pity to throw it away as garbage. Then, we bought it from the friend to save him and the sword itself. We will try to help the sword, to have it re-hardened by our smith. But still, we are not sure if it could get new hamon or not.
We asked another friend who has very clear eye to check this katana. He studied it carefully, and suggested us to make a part polishing on it before re-tempering challenge. He was afraid if hamon exists under this horrible polishing. Then, we decided to follow his advise. We brought it to a polisher to do that.
Some weeks later, the part polishing has done. Unfortunately it has no hamon in most of the blade. Then, we decided to try re-hardening.