The Weathered Copper Chest is the third oxidation stage of the Copper Chest, displaying a green hue with light brown patches as the metal continues to corrode. It functions identically to the regular variant, serving as a 27-slot storage block that can merge with another to form a Large Copper Chest containing 54 slots. Players can prevent further oxidation by applying Honeycomb to create a Waxed Weathered Copper Chest or restore it to a previous stage using an Axe.

The Weathered Copper Chest can be crafted by allowing an Exposed Copper Chest to oxidize further over time or found naturally when a Copper Golem is created using a Weathered Copper Block. Its oxidation only affects appearance, not functionality. Like other chests, it can be opened unless obstructed by a conductive block, renamed with an Anvil, or locked using commands. Copper Golems can interact with the Weathered Copper Chest by retrieving items and transferring them to nearby Wooden Chests, making it valuable for automated storage systems. The chest must be mined with a stone pickaxe or better to drop itself.