Járngreipr

In Norse mythology, Járngreipr (Old Norse "iron gripper") or Járnglófi ("iron gauntlet") are the iron gloves used by the thunder-god Þórr. According to the Prose Edda, along with the hammer Mjǫllnir and the belt Megingjǫrð, Járngreipr is one of Þórr's three crucial possessions.

Uses
According to chapter 20 of the book Gylfaginning, Þórr uses the gloves to handle the Mjǫllnir.

Origin
Þórr uses the gloves to wield Mjǫllnir, therefore the origin of the gloves and the reason for this may come from the forging of the hammer, when Brokkr, the dwarf working the bellows was bitten in his eye by a gadfly (commonly held to be Loki in disguise) which caused the handle of the hammer to be shortened.