Civil War era Minié (or Minni) ball bullet, used in muzzle-loaded rifled muskets. The bullet is made from lead and has a deformed, rounded shape instead of the conical one it should have; there is a set of three grooves around the base; the bullet itself is lightweight and hollow, an intentional design created to cause the most damage possible. There is a white patina (lead carbonate) covering the entire object, this can be caused by exposure to carbon dioxide and is a normal sign of age; the object is deformed but does not appear to have been shot, the top is rounded with two deep indentations and the base is malformed, no longer circular.
Three bands on its shank. Very deformed. The bottom is pushed together and there are many scrapes as well as a large divot on its sides.