I went back out today for 3 more hours. Found another $8 in coins, a cigarette lighter, a toy bracelet and these 4 rings.
Actually, the Final Fantasy ring is from a necklace that costs about $18. I didn't find the necklace. The rose ring has a small inscription that I think reads "cz6S" but I'm not 100% sure (see below). There is no gem and I thought cz was only a fake diamond, not a metal. Any ideas?
I also met a women who claims that her friend lost a very valuable gold ring yesterday with a huge gem in it. She asked me to search for it next weekend and I agreed. If I find it, I'll post a pic.