I've no doubt that the chevron strand you show is Venetian, newer for the European market. The clasp style is characteristic. I've got a nicely knotted strand of ""wedding cakes" somewhere with the very same clasp. I'd think no older than 1970s, or thereabouts. But to clarify, I am not looking just at the clasp. The beads are Venetian.

Chevrons still made there? There are probably a few individual small businesses still producing very small volume, but also I believe Moretti still produces small ones. Hopefully Rosanna can tell us a bit about it - she was there recently.