Prometheus Ring, copper, Arkansas river stone
"For his impious daring in stealing fire from heaven for mortal man, Prometheus had been doomed by Jupiter to be chained for 30,000 years to a rock in the Caucasus, while a vulture fed upon his liver. Before long, however, Jupiter relented and liberated Prometheus; nevertheless, in order to avoid a violation of the original judgment, it was ordained that the Titan should wear a link of his chain on one of his fingers as a ring, and in this ring was set a fragment of the rock to which he had been chained, so that he might be still regarded as bound to the Caucasian rock."
-text from Rings For the Finger, published in 1917.
If you are interested in jewelry do check out the book. You can download the entire scanned document for free as a pdf or as a searchable text-only file, and you can also read it online. Open Library has a number of public domain historical and instructional jewelry making books that I've loaded onto my iPad. I was reading about prometheus' ring while I was out getting new tires this week, and it seemed the perfect symbol for my recent RAD lag. RAD drag. The pain and tedium of the repetitive event and the feeling of being chained to RAD.
Tonight I finished another piece incorporating local stone: