Right click Copper Golem to take held item.

The Copper Golem tends to break when it can't find a chest for an item, which is annoying, but just get some more of that item and put it in the chest, no biggie. However, this is especially problematic when it's holding a unique/rare item. Suppose you want ol' CG to put away some wind charges, but, oh no, you don't have any in a chest! Now you have to travel back to that Trial Chamber you found 2000 blocks away, just to get some more. Solution? Simple! Just right click to take the item it's holding. :)