I dug this up from about 5 inches in a forest preserve very near where I found the silver ring. There is no design on the back and I would guess it to be made of something like pewter. The trinket and small bronze or copper ring were also in that area. The ring isn't the sort of ring someone would wear so I'm thinking it might have a gasket. It looks like a tiny diamond in the trinket but it doesn't sparkle like one. Probably glass or plastic.