@Mordred,
As long as you don't get too fixated on pigmentation and have lived among us, it isn't that hard. I can be fooled by a few people in the extreme north or the extreme south, who overlap with people from different areas, but even in those cases I'm aware they could still be Italian, because I've seen the features before. I agree, fwiw, that once Damiano grew into his bone structure he couldn't be anything but Italian imo.
@Duarte,
You're so often on point because you've lived among the descendants of Italians from Rome north. A lot of Americans, in particular, have no idea what they look like. I didn't need to look up "Elliot Stabler's" real surname to know it was highly probable he was Italian. I'd seen variations of his face before.
I think your point about the pronounced masculine features in a lot of Italian men as they grow into maturity is very good. It's as if the facial bone structure sort of "pops out".
It's not always the case, of course; we have our soft faced men too, and it's something that one can see particularly in Emilia Romagna, imo, accentuated in age by portliness as the result of the rich food.
For example, one of them, a blues singer, Zucchero, had that "soft" face even when young and thin.
The reason I'd know him is that half my father's family looks like him, especially my aunts.
This is Umberto Tozzi, another singer, who seemed to have somewhat more pronounced facial bones when young, but his face also got softer with age; perhaps weight had more to do with it in his case, and loss of muscle tone, which may go with that "softness" of face.
Southerners too can have rounder features, of course, but it usually seems to me that unless obscured by fat, or they're very young, their features still have a somewhat "bonier", more masculine appearance as they age.
This is one of the Northern Italian actors who says he couldn't get work here because they didn't think he looked Italian and they couldn't explain the accent if they cast him. Go figure.
I'm currently watching him in a not very good Italian tv series on Amazon Prime. Still gorgeous...good bones never fail you.