Powder Flask, c. 1550-1580. Powder flasks are small, portable containers designed to hold gunpowder. From the 1400s to the 1800s, powder flasks were indispensable for charging and priming firearms of all types. Without powder flasks firearms were of little use to their owners. Many highly decorated flasks rank as works of art. During the 1500s, they were frequently decorated with images of famous historical figures. Here the figures of the Judgment of Paris come from Greek antiquity.