"Sparky." Also Sindri. A dwarf, one of Ívaldi's sons. He and his brother Brokkr fashioned many of the god's prized possessions: the golden hair of Sif, the ship Skíðblaðnir, and the spear Gungnir. Loki wagered his head with Brokkr that Eitri could not make three other precious thins equal in virtue.
The brothers accepted the challenge. Eitri began his work in the smithy and set Brokkr to blow the bellows. Loki assumed the shape of a fly and tried to hinder Brokkr while Eitri fashioned the boar Gullinbursti and the ring Draupnir. The fly then stung Brokkr's eyelid and when blood fell into his eyes, the dwarf clutched at it while the bellows grew flat. Eitri said that all that was in the hearth was nearly spoiled. Then he took from the forge a hammer, which came to be known as Mjöllnir.
The brothers took the precious gifts to the Æsir and the gods judged that the hammer was Eitri's best piece of work, even though the haft was somewhat short, since it would be their greatest defence against their enemies the jötnar.
- Skáldskaparmál, 35.