Interesting... Years ago, when I lived in Vicksburg, I visited Poverty Point, across the river. If you've not had the chance to visit those mounds, it's pretty kewl. Anyway, it was a drizzly, cold day there and I was the only visitor, so I did some exploring. Among the things I spotted were a handful of lead thingies, like yours. They were near each other on a creek bank and I believe they may have been part of an article of clothing. They look like they were pressed into place somehow.