Diamond helmet is the middle tier of helmets which can be equipped. While wearing it, player takes less damage from mobs, spikes and other players. The protection provided by the diamond helmet is higher than the golden helmet.
They are upgraded from the golden helmet and can be upgraded to an amethyst helmet. Upgrading to the diamond helmet takes 1 minute. It is strongly advised that players have an IKEA Manual in hand before crafting. If an IKEA Manual is not available, make sure to have full food and cold bars with substantial cold protection.