Ihatepoisonivy sent me a Private Message, asking me to comment about the iron balls she found.
The number-one test for determining with CERTAINTY whether or not an iron ball is an Artillery ball (cannon ball, Grapeshot ball, or Canister-ammo ball) is to do super-precise measuring of the ball's diameter. I invite any readers who want to learn how to do the super-precise measuring, and learn a lot more about Artillery balls, to read an educational article (with photos) I co-wrote with David Poche, here:
SolidShotEssentialsMod
Artillery balls absolutely HAD to be the correct diameter size, in hundredths-of-an-inch (such as 3.58-inches), in order to fit into the cannon's barrel snugly but not TOO snugly, or they would not fire properly (and could even cause the cannon to burst). So, if a ball's diameter isn't within a couple of 1/100th-inch of the correct size, it is definitely not an Artillery ball. Go to the following link to read the super-precise measurements of actual Artillery balls specified in the US (And CSA) Ordnance Manual Of 1861 (which covers the sizes of American, British, and French Artillery balls used in America from the Revolutionary War through the Civil War):
www.civilwarartillery.com/shottables.htm
Now, all of that having been said:
Ihatepoisonivy said the balls are "about" 3.5-inches in diameter. That is too large to be a Grapeshot ball or a Canister-ammo ball, but could be a cannon ball. The photos show that they are "unfinished" castings, having a RAISED mold-seam on them. Although many actual cannonballs came out of the ironcasting mold with a raised seam on them, the raised ridge was always removed from cannonballs at the ironfoundry during the "finishing" process, because the raised ridge could cause the ball to be a bit too big to fit into the cannon's barrel. However, there is no need to do the labor of chiseling off the raised moldseam on some kinds of Civilian-usage balls, such as Mill-Balls.
Also:
The balls in the photos show a chiseled-flat circular area, which in this case is a casting-mold's "vent hole" mark. I've never seen such a WIDE vent-hole mark on any Artillery balls which are "about" 3.5-inches in diameter.
In summary:
The balls found by Ihatepoisonivy are "about" the right size to be a cannon ball, but they show two characteristics (raised ridge, and extra-wide vent-hole mark) that are not seen on actual cannon balls. However, the ultimate test is super-precise measuring. The "nearest" size of actual cannonball is 3.58-inches. If these balls do not measure 3.56-to-3.60 inches (not counting the raised ridge), that would prove beyond any doubt that they are not cannon balls.