If so, where did they get it?
If not, what did they use instead?
I can't answer as to the Black Sea, but I've written a bit about ancient mining in what is today Oman and Jordan here that may be of interest: https://www.reddit.com/r/AskHistorians/comments/4hp90c/as_far_as_artifacts_go_how_significant_is_slag/d2rfs3f/
The Jordanian mines, as I understood from a local guide, were Roman and so a bit later than what you're talking about, but the Omani mines are from the Bronze Age and were for export production.