I know we have a lot of stuff here in the eastern part of Tn western NC but I can't tell the difference between a regular rock and a gem encased in stone. It's not like topaz or aquamarine that comes out of the ground looking like a gem, garnet, emerald, ruby and such just looks like a rock until tumbled or cut. That's the hard part. The guy shined a light through them and looked at the color and told us what gems they were but I'm sure it takes a trained eye to know what you're looking at....something I don't have yet.