That is the mother load, awesome!!! Maybe you can research the site over winter and find out more about them. I thought my two cannon balls were great but 679, whoa, LOL! HH and a big congrats, Mike
Cool finds indeed....but to me it looks like a win-win situation for you. If they are mill balls and not cannon balls they 1.) are still historic and; 2.) you must be pretty darn close to a big mine of some kind. I can't imagine that if they are mill balls that someone would just be carrying them around for something to do . They were there for a purpose rather it was a Ammo depot or mill area of some sort still pretty cool to have and to have found. Post the pics of the area as long as it won't give the location away, else you might go back in the spring to an empty site. Like the others have said W& ET definitely.
I thought that these had already been confirmed as projectiles. If not, maybe there's an easy way to settle this "Cannonball" vs. "Mill Ball" debate. From your other post, I know that you've weighed and measured the various sizes. Why not send the photos and specifications to Jack W. Melton, Jr., coauthor of Civil War Artillery Projectiles, and see what he says? I'm sure he'd be interested in your find... especially if the subject header for your e-mail is "679 Cannonballs Found!" There's also a ton of info on his website.
I have a fair amount of mining in my background, and I'm thinking (contray to most) that these are milling balls. Thats primarily because of the different sizes. In milling rock different sizes are used with different size rock to be milled.
It's a very good find, but i would take care before offering for sale to finish the detective work
High adventure!!!!!!!!!!!! I would love some pics and history on the location. That is amazing. I have three cannonball s and it took me a good while to find those. Keep the information coming. Congrats.