Vintage Screw On Earrings Marbled Sea Green - Unusual Material Possibly Glass?

Description

These earrings measure halfway between 5/8" & 3/4". Statement earrings. I am unsure of the material, is heavier than I would expect plastic to be. Both earrings weigh about 0.5 oz together. Rear has some tarnish/discoloration and a little bit of glue visible. Preowned vintage earrings, sold as shown - I am unsure of material type(s) because of this. Pictures show different angles for you to review - while I attempt to note any defects, some tarnish/signs of wear may be visible that are not otherwise stated. Earrings are tested and photographed on a thin/smooth earring stand (not included) to show that the screw backs are in working order.