These are coffers containing treasures that are found in some dungeons throughout Vana'diel. Coffers are typically in higher level areas and have better contents than Treasure Chests. In order to open a coffer, you either need the appropriate , or need to be a Thief with a lock-picking tool. The keys to open the coffers are dropped from specific mobs, which are usually located in the same zone as the coffer. When you open a coffer you will either randomly get one of the possible items, some gil, or a quest item if you have a pertaining quest active.