In Ancient Egypt during the reign of Ramses II, an alchemist discovered a fallen meteor and took a shattered fragment which he used as the headpiece to a scepter. He presented the scepter as well as the rest of the meteorite to the pharaoh Ahk-Ton. The scepter was named the Orb of Ra. Exposure to the radiation from the meteor had a transmutative effect on Akh-Ton's body and he became the first Metamorpho. 
Ahk-Ton sent the Orb of Ra into the future, calculating for its return as a powerful weapon against the king. When Batman and the Outsiders arrived from the future, Ahk-ton used the Orb to enslave Rex Mason, the current Metamorpho. Once Metamorpho was freed, Ahk-ton was defeated and taken by Ramses, who intended to slay Ahk-ton. Apparently this execution was stayed. Ahk-ton soon resurfaced. This time, he himself had been transformed by exposure to the metor into "the Metamorph."
Vandar Adg (Vandal Savage) used the Orb of Ra to enslave Ahk-Ton and war against the prince, Khufu. This transformation was later reversed, and Ahk-Ton slain and buried along with the artifacts.
Millennia later, Rex Mason, a soldier for hire, was contracted by Simon Stagg to find the Orb of Ra. When he found it, his cohort, Java, stole it and left Rex in the light of an ancient meteor. This meteor transformed Mason into Metamorpho, the Element Man. Soon after, he sought the Justice League's help in restoring him to normal. This failed, and Rex also rejected the JLA's offer of membership. He teamed on other time during the "Silver Age" of heroes when Deadman coerced a group of heroes to form a task force against Agamemno and the Injustice League.
The Orb of Ra eventually came into the hands of Simon Stagg who used it to manipulate Metamorpho into continuing to work for him.
Years later, a member of the Irish Republican Army named Peter O'Grady stole the Orb of Ra and sold it to an Egyptian collector named Delacroix. Delacroix, in turn, sold a fake version of the Orb to Emir Abd-Al-Aziz. Delacroix had the Orb for only a short period of time, and it was returned to its original resting place in the Pyramid of Ahk-Ton in Egypt. Simon Stagg hired the metamorphae Jillian Conway to recover the Orb. He intended on using it to cure Metamorpho, thus making him vulnerable to attack. What Jillian failed to tell him though was that the restorative power of the Orb could only be used once. Intercepting Metamorpho in Egypt, Jillian gained possession of the Orb and attempted to use it to cure her own condition. Conway mis-interpreted the instructions on the hieroglyphics though. Instead of reversing her elemental transformation, it actually completed it, ultimately killing her in the process. 
Links and References
|Characters||Metamorpho | Sapphire Stagg | Element Girl | Joey Mason | Shift | Element Woman ||
|Teams||Justice League America | Justice League Europe | Outsiders | Doom Patrol|
|Villains||Simon Stagg | Java | Doc Dread | The Thunderer | Maxwell Tremaine | Ahk-Ton | The Phantom of Washington | Jillian Conway | Kanjar Ro|
|Miscellanea||Metamorphae | Elemental Transmutation | Orb of Ra | Stagg Mansion | Stagg Enterprises|
|Creators||Bob Haney | Ramona Fradon | Sal Trapani | Mark Waid | Graham Nolan | Dan Jurgens|
|Comics||Metamorpho (Volume 1) | Metamorpho (Volume 2) | Metamorpho: Year One | Batman and the Outsiders (Volume 1) | Batman and the Outsiders (Volume 2) | Outsiders (Volume 1) | Outsiders (Volume 3) | Justice League Europe | Legends of Tomorrow (Volume 1)|