Nebuchadnezzar II, also Nebuchadrezzar II, meaning "Nabu, watch over my heir", was the second king of the Neo-Babylonian Empire, ruling from the death of his father Nabopolassar in 605 BC to his own death in 562 BC. From Wikipedia
The bricks, dating back to the reign of Nebuchadnezzar II, reveal a dramatic shift in the magnetic field, opening up new methods for dating ancient artifacts.
