I was given a metal detector at 10yo. I had no idea how to use it and I would pretend I was looking for treasure (or I probably believed I was). Now at 31 I finally purchased a minelab 350 somethin or other. So far I've been out about two hours. Found some penny's! (One all copper!), a sprinkler head, some pop tops, two hot rocks and this saucer shaped metal pellet. It looks like a large rivet or even the head of a round bolt. Its very heavy for its size. Its not magnetic. If anyone has any idea what it may be please let me know. I will post a picture.