New shamshir: hoping for a diamond in the rough.

[10thRoyal]

Originally Posted by mariusgmioc

To me it looks like Persian wootz.
Why doesn't come out as in high contrast, I don't know as it can have many causes.
I found out the best etching results are on surfaces polished to 2500-3000 grit. Higher polish gets worse results as the etchant does not "bite" the surface.
I got best results with Nital 4% but this needs to be top quality etchant. I found out that some Nital suppliers don't respect the advertised concentreation and you don't get the expected results. Most of the times, I needed to apply Nital more times.
As for the last few years I wasn't able to get Nital anymore, I started experimenting with ferric chloride, in commercially available concentrations, then diluted but without any rigurous measuring. Got generally good results with ferric too.
I found out that even on the same blade there may be areas that display hugh contrast wootz pattern and some areas that won't display any pattern at all or a very faint one.
My guess is that if the blade is reheated it may loose partly or completely the wootz pattern. I suspect this may be the case of your blade.

Nital is what I have the most experience with so that's why I gravitated towards it. I have a Material Science degree and have etched and polished more metal cross sections than I want to remember. For my last few etching attempts I only used nital that was mixed fresh to avoid any degradation of the ethanol. I know that Everclear and gold testing solution are exactly lab grade but SDS for the gold testing solution showed it as being 50 to 70 percent nitric acid, with some sds's showing the addition of a few percent hydrochloric. All in all it should give a nearly identical etch to lab grade nital. I found that the ferric chloride etched metal oxidized almost immediately with contact with air, leaving a nasty brown finish.

The reheating causing a loss of contrast is an interesting thought for sure. One interesting thing I noticed from my earlier etches which were way over etched was the near lack of wootz figuring near the blade spine. I'm wondering if the spine was heated at some point. Or potentially the spine is a different steel all together. In the photo posted below, the spine is to the right side of the image.