Vintage Large Green & Black Swirl Mod Pendant

Mod pendant from the 60's. The center piece is not stone, but it might be glass or resin. The pendant itself is very heavy, & the majority of the weight is from the frame, but the green black-and-white center, feels like the type of thick plastic, when I tap it. The pendant is large. About the size of an Oreo. Really unique framework. Has kind of like, flattened spikes & a lot of texture to it. Not sure what type of metal it is. Has normal age wear to metal.