The Scion that was found in The Tomb of Qualopec by Lara. each of these pieces were worn around the necks of the Atlantean Gods Qualopec, Tihocan and Natla and could only be used once all three piece's were put together.The Rulers casted the three pieces of the Scion in separate locations so that it could never be used after their eventual death. It was last seen in Atlantis.
The size of the model is roughly the size of a CD as from reference images it appeared that way. *Important* You will need all 3 pieces to complete your model as Natla's is the hub :)