I don't think anything is truly abandoned up here; it all belongs to somebody. Lots of this area is national forest and they've started putting up signs warning about removing archeological and historical relics. Check with the national forest folks. When I'm out, I'm always prospecting, which I believe is legal, unless I'm on someone's claim. I've never been confronted by a Ranger. Better yet, call up Gold n Detectors (sp?) in Golden, CO. They're pretty good old boys and would probably answer your questions. And I don't work for them or nothin, but I guess I'm givin them a free plug. I done business with them and they treated me alright.