Red cents are the ones that are brand new and mint state. This kind of red, is a form of environmental damage. A rust that makes the coin look red. It was probably underground at some point. I had a photo of some very red ones that I dug up, but of course I can't find it. The 1964 penny in the center, and the dollar coin on the end. And the red Sacagawea.
Very nice. I like the Native American dollars. My red Sac is ED I dug it out of some sand and it had been there a while.