To me, vintage costume jewelry are just as beautiful as their more expensive siblings. I personally prefer to wear costume jewelry over the real stuff. Giant cocktail rings, bead cluster earrings, enamel painted brooches...YES PLEASE!
Popular 'Vintage Costume Jewelry' labels/designers:
Coro, Avon, Trifari, Monet, Napier, Miriam Haskell, Lisner, Le Bernard, Kenneth J. Lane, Kramer, and Schiaperelli.
I have carried these designers at Adore Vintage at one point or another along with many unsigned pieces and lesser known designers.
Sources: 1.] Vintage costume jewelry from Adore Vintage