Cheese is on the right track in his comments. The very first cannonballs ever made, back in approximately the 1200s, were stones wrapped in cloth. But as he indicated, people soon realized it is MUCH less laborious to make an ironcasting mold and produce hundreds of just-the-right-size cannonballs pretty quickly that way, instead of trying to chisel each one down to exactly the right size (and shape) out of a piece of stone.
Therefore, ever since then, NOBODY made cannonballs out of stone. Claims to the contrary are incorrect. (For example... no, the Europeans did not use stone cannonballs in their conquests of the Americas.) Trust me, if people are capable of casting an iron cannon, they are also capable of casting iron cannonballs. Those people are NOT going to do the grueling labor of chiseling each ball (which MUST be the exact same diameter as the others, and perfectly-round) out of stone.
Because you found your stone ball near some Indian ("Native-American") artifacts, it may be an Indian game-ball. You'll need to take it to a college's Archeology Department for examination by a pro, in real-life. (As a former Archeologist, I have to tell you that photos are often not adequate for certainty in identifying stone artifacts.)
