450 Million Year Old Fossil Used to Make a Native American Necklace

This a 450 million years Crinoid fossil that Native American's turned into a necklace. I was working on a deep auger, Geo-Morphology project and found about fifty of these. They varied in size from about 3 cm to 1/4 cm. In the middle of each of them was a carefully drilled hole. 

I also found two pieces of twisted bone. Both measured about 8 cm in length. After doing some research I discovered this would have been the centerpiece. The Crinoid beads would be arranged from widest in the center and smallest near the shoulders. 

The area I was working in had been a mound but an idiot farmer bulldozed it. He decided he needed a new metal barn and didn't give a crap about the history he was destroying.