Good resource on
Armi Bianche Italiene, Jim. How did i fail to consult it ? Definitely my alzheimer quota is greater than yours

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Indeed the examples are numerous; example #550 has a pommel similar to the one in mine ... do i see it right ?
I take it that calling these
Pungnale da duello is just an option for a different name of the same parrying / left hand / main gauche / mano sinistra weapon. I like the portrait of the Cavaliere di Malta ( #568/569 ) bearing one of these on his waist.
Indeed the ridges have rather varied designs ... many more than i thought before. It could then be a sort of signature of the smith ... or a symbol typical of each region ?
One thing i guess we should put apart is its use for sword (tip) breaking; in a quick test i notice that the ring is not "flexible" enough to lodge the different blade widths and, above all, you would have to cut your hand to let the opponents penetrate in the ring, which id a not a plausible move

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Still i have this fixation that, despite its varied shapes, those ridges resemble an aiming sight. Oh forget it

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