The eel figurine was an Atlanteans device of unclear purpose. It had the form of a coiled serpent with an open mouth; inserting an orichalcum bead in the orifice would raise the temperature of the artifact's mass.
An eel figurine was uncovered in 1939 in Iceland by Bjorn Heimdall who believed that the country was used by aliens as a spaceport to establish colonies such as Atlantis.
After Heimdall froze to death, Indiana Jones freed the artifact from the ice by using an orichalcum, and traded it with Felipe Costa in exchange for information on Plato's book.
A similar relic was found in Atlantis in an alcove in one of the rooms of the outer ring. At the flooded doorway, Jones inserted an orichalcum bead in its mouth and throws the searing hot figurine to evaporate the flood waters, deteriorating the figure into scrap metal.