Antique looking necklace

Hello I’ve just rediscovered this lovely necklace that I didn’t know I had, don’t remember it but I’ve just had a look and it looks quality, not attracted to magnet apart from the clasp, had a look with a loop and can’t see markings but lots of verdigris, the kind I normally see on antique items, not sure what the little gem stones are and looks like it had a gem stone glued to the front, I think I have loose stone that would fit this, not sure what it had originally, maybe someone knows more about it.