The loot that a Skyware Chest can contain includes one primary item, one secondary item, and a host of common items. The primary item in a Skyware Chest is more deterministic than most other loot-containing chests. Similar to Locked Golden Chests, the first chest to be generated in the world will always have the first primary item, the second will always have the second item, and the third will always have the third item. All floating island houses past the first three will then have a random primary item. Therefore, the vast majority of worlds will generate at least one copy of all 3 items. All Skyware Chests have an equal chance of containing the Sky Mill.