Steam Punk Metal Necklace

I think this might be brass but not sure. It’s an artistic style long necklace with a primitive steampunk vibe. Casual,Cool 26”(13” hang, doubled) long chain til large disc with a total of 21” length. Could use a cleaning, polishing. See pics. They are part of description. Thank you. I accept reasonable offers and don’t hesitate to ask any questions.