Civil War era Minié (or Minni) ball bullet, used in muzzle-loaded rifled muskets. The bullet is made from lead and conical in shape; 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. A white patina (lead carbonate) is present on much of the object, this can be caused by exposure to carbon dioxide over a long period of time and is a common sign of age.