The oxidised full helm is a quest item used in the Dealing with Scabaras quest. It can be made by using a bucket of Ugthanki dung on a bronze full helm while standing in the Kharidian Desert. The oxidised full helm's given colour in the game is based off the gases (mainly oxygen) in the Ugthanki dung causing a chemical reaction with the copper of the bronze full helm. This causes the helmet's change from normal bronze colouring into an copper oxide coloured full helm.
It cannot be made again after the quest with attempting to do so resulting a chat box message stating "There's no point in distressing any more items. Simon has had his delivery of bronze artefacts.".
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