The Stones of Power, also known as the Stones of Knowledge or simply the Elements, were three Kryptonian crystals containing all the known knowledge of the 28 galaxies. Their power was well-known on Earth and they were sought out by many occultists and practitioners of magic. When Clark Kent united all three stones on the Kawatche Caves altar, the crystals transformed into the Crystal of Knowledge, which was capable of creating the Fortress of Solitude.