I checked out this book from my school library when I was in upper elementary, 1971-1973, so the publishing date could be ’50s, ’60s, or early ’70s. I seem to remember a cream colored dust jacket, with black and white illustrations inside that resembled cave drawings. The girl kept her bits of metal under her pillow to keep them safe. I seem to remember a leader wearing a cloak pinned with metal and also wearing a torc around his neck. I don’t remember any psychic abilities or romance in the plot. It’s not “The Cave Twins” or “The Distant Lurs.” (I’ve gone through *most* of the queries until my eyes crossed. 😜) It might have been set in Britain, maybe another European country. She may have saved her owner’s clan by warning them of an imminent attack. And I think she was indeed able to purchase her freedom at the end of the story. Sorry, the details are very fuzzy but I checked the book out several times and loved it. (Probably one of the books that started my love for strong female characters.) Thanks in advance for your help!