Promethium X was an element from space.
Promethium X was an element from space. However, it was also a resting place for alien lifeforms called symbiotes.
The Promethium X was found by John Jameson on an asteroid in space. Upon removing it from the asteroid's surfce the ground began to bleed a black liquid. Jameson then got to the shuttle with the Promethium X and began to head back to space.
Upon studying the Promethium X, Jameson learned that it was as powerful a plutonium and could be the answer to Earth's energy problems.
Eventhough Promethium X was radioactive it only became radioactive when exposed to extreme heat.
Kingpin intended to sell the Promethium X but it was stolen by Spider-Man.
Kingpin later had John Jameson kidnapped and planned to trade him to Spider-Man for the Promethium X.
When Spider-Man studied the Promethium X he learned that its radioactive life was only temporary and would eventually transmutate into lead. Knowing this Spider-Man gave the Promethium X to Alistair Smythe withhout a fight.
When Smythe examined the Promethium X he saw that it had turned into lead. Kingpin then realized that Spider-Man knew the Promethium X would turn into lead and that he allowed Shocker to take it.
- Promethium X is based on the real life element, Promethium.