Hand Tools Archive
Toughness is measured how, and is it always the same at 33 degrees at a tiny edge as it is on a 90 degree edge of a die?
Silica, yes. What I'm getting toward is that you mention toughness being better presumably than O1, but in maple, the two carbon steel irons took much less damage from the inclusions.
Is it silica causing the problem in rosewood? I don't know. There's no iron, no matter how much vanadium is added, that holds up well when there are little silica particles. Some holds up better than others, but the damage is nicking and not abrasion. Those green chinese blades do OK, but I've learned over the years that in really difficult wood, giving in to sharpening more often is generally far more productive. Increase the shaving thickness, set the cap, get most of the work done and use a fresh iron to do the final few passes.
Sometimes changing the method is better than changing the tools.
Fairly large chance that part of the issue here is the iron that I kept for myself (because I didn't like the way it looked after heating it too long - a good lesson learned, as it confirms that for household heat treating, get it hot and fast as quick as possible, then quench. Don't chase a little bit of extra brightness in the color hoping for additional hardness).
I could go down a rabbit hole here discussing what's preferable, but a test of O1 vs. the commercial V11 on some of this rosewood (hopefully the second billet is identical to the first) will settle it.