Is there a little ding or notch carved in it or not? If there is it is a bolo ball if not it is a gamming ball and yes it is an artifact . Battle field? Most battle fields were villages where massacres took place as at Wounded Knee where they nearly wiped out Chief Big Foot and his people on december 29 1890.only a handfull survived out of 300 . Most Battlefields were villages and a good place to look for artifacts .Good Find Grasshopper Bob