Iron is a metallic element, that posses strong supernatural properties, and is thus used mostly by hunters, when combating against supernatural creatures.
Creatures that Iron effects
- Demons- to touch iron burns a demon, they also can't cross iron, mutch like salt. There weakness to iron is so strong, that even Azazel, one of (if not they) most powerful demons ever to exist, who was immune to many other demon weakness, was still effected by Iron. The only known demon to be immune to Iron is Samhain.
- Ghosts- To be stabed or shot by iron, will temporalily make the ghost disapear, they also can't cross iron, much like demons. Sam and Dean considered cold iron to be the best way to repel vengeful spirts.
- Faries- All faries are weakened by iron, although powerful ones like Leprechaun's can shrug it off.
- Phoniex- Iron burned the Phoniex's skin, and it couldn't touch Iron, or if imprisoned by it, escape.
- Leshi- The only way to kill a Leshi, is to cut of its head, with an iron axe.
- Shtriga- Iron is the only thing that can kill a Shtriga
Iron also effects humans, who enter full astra state, exactly the same is it does to ghosts, they can be imprisoned by it, to touch it causes them pain, and makes them temporaily disapear, although like ghosts, the only reapear inside the iron prison.