Ah, very interesting Maarten- so rarely is important information such as metal thickness given that it's quite interesting to get first-hand data, thanks
0.06mm seems so very ridiculously thin for a functional object, even if backed with solder- I have some sheet brass that's 0.12mm thick and it's just thick foil, hardly good for anything I'd thought. I'd actually have even found it hard to imagine the flat, silvered base plate being that thin.
Obviously yes, Brian, some few objects were made using thin sheet but on a supportive backing plate- the Pompeii balteus plates, or the embossed style
Gladius pompeiiensis scabbard elements- however the Tiberius clearly has nothing behind it's locket section (judging by the holes), so it's not the same thing at all- there is no support for what is essentially foil that could be dented with the slightest knock. It's not exactly a likely expectation given the thicknesses of other scabbard elements either- the locket section of an earlier
G. mainzensis type sword with pierced decoration I examined was on the order of 1.5mm thick and a
G. pompeiiensis chape was 0.5-0.6mm thick. But the extreme thinness of the Tiberius certainly explains why there are no chasing marks on its obverse- there's certainly no way to make such clean decoration by hand in thicker metal without chasing and that always leaves telltale signs.
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