A Silver Jug is a miscellaneous item found in The Elder Scrolls V: Dawnguard. It resembles the very common silver-colored version of jugs found all over Skyrim, but it differs in that its spout area is permanently stained with blood. Its only use to the Dragonborn is as a collectible unusual item.
Silver Jugs can be found on the tables in the dining area of Castle Volkihar. At least 4 can be found and can be picked up as early as the first visit to Castle Volkihar, if the conversation with Harkon is interrupted while the Dragonborn explores and collects items.