"Said to be an ingot of the legendary metal orichalcum. Plato noted its presence in the city of Atlantis."
This unique salvage item is found by the player using the clues from the treasure rumor titled "Okeanos Tablet 1" in their notebook. The treasure rumor is only triggered when the player finds the Cavern of the Gods the first time around in the main storyline. However, the player can find this treasure before the end of the main storyline by using the Multisensor the first time they are in the Altar of Horus. The ingot is found in front of the statue of Horus.