According to Catholic Online, "Saint Barbara, also known as the Great Martyr Barbara, was an early Christian Greek martyr born mid-third century in Heliopolis, Phoenicia. St. Barbara is depicted with mini chains, standing by or holding a tower with three windows, carrying a palm branch, and sometimes with cannons. She is the patron saint of armourers, artillerymen, architects, mathematicians, miners and the Italian Navy. St. Barbara is one of the Fourteen Holy Helpers, venerated because their intercession is believed to be particularly effective against diseases. Barbara is often invoked against lightning and fire, with associations of explosions. Her feast day is celebrated on December 4."