Hi all!! Well I was so curoius that I can't wait: I have tried but don't seems to be twisted core..... I'm so sorry, I was hoping.... Anyway I haven't taken pictures because it wasn't worth. I have polished and etched twice one side of the blade, one time with cloruric ferric and than with lemon, but nothing. Anyway I will try again on the whole blade with vinegar.... The last chance