Hi! Yesterday, a volunteer let me know that she had found what she believed to be Astraspis and Eriptychius fish scales. She collected a few pieces to get under the microscope and sent the images to me. Unfortunately, I have no experience with early fish fossils at all. I do believe the rock to be Harding Sandstone, which would be the right age for the fish. If someone with early fish knowledge could weigh-in, I would appreciate it. The material comes from Southern Colorado. Thanks!

P.S. The pictures were too big to attach so here's a link

http://imgur.com/a/mZFwf

Sorry but no one seems to know the answer to your question.