Loki had the gnomes make him a magic spear and a boat that would sail anywhere, and could fold up small enough to put in his pocket. He also had them make a cap of golden hair for Sif.
Loki, who was known for his mischief and desire to cause trouble, cast a sleeping spell on Sif and cut off all of her beautiful, long, blond hair.
You must sacrifice your eye.
ODIN'S EYE
The Mystical Well of Urd has magical waters that give one the gift of cosmic knowledge.
Odin was always on a quest for more wisdom. When he arrived at the mystical Well of Urd, the guard, Mimir, told him he had to sacrifice an eye in order to drink from the well.