The decanter, weighing 8kg and 60cm long with a leather-bound shaft and engravings, was stolen from a CBD bar on Saturday night.

Police released images of a group of men they believed could help lead them to the custom-made decanter, shaped like Thor's mystical hammer from the popular superhero franchise.

On Friday, investigators found the hammer-shaped bottle at Melbourne Airport.

A 52-year-old man from Mindarie, WA, presented himself to Perth police station a short time later and is assisting police.