6 Vintage Screwback Mexican Silver Earrings These are sadly missing mates (at least so far! Cleaning out jewelry boxes.) Two on bottom have markings (silver/Mexico), the one with the green stone and the square etched one. The others, which are cloisonne or enamel, and the one with the faux purple stone, are not marked at all. Beautiful earrings, hoping someone can use for an art project. Have not tried to clean/polish them.