Vintage earrings?

Flea market find. I would like to know more about these earrings - I am not even sure if they are vintage, or not. I found no markings. I found out that similar findings were used in 1960s but the earrings are in pristine condition, they are nicely done, smooth, heavy, glass stones. Pretty heavy for my earlobes to wear for a longer time.
I also noticed that I cannot just take pliers (jewelry making is my hobby) and split the bindings and take out the bottom part - there is no gap in the metal rings at all, it looks like sealed in one piece so I suppose this is a good quality costume jewelry?