Star-Forge
The Star-Forge is a forge on Nidavellir, operated by the Dwarves. It is powered by the neutron star around which the ringworld of Nidavellir orbits. Because of the importance of craftsmanship to Dwarven culture, the King of the Dwarves and the master of the forge are always one and the same.
The Star-Forge is the only forge in existance capable of working Uru due to the intense temperatures and quasi-magical nature of the Forge itself. Gungnir, MjĂžllnir, and Hofund were all created in the Star-Forge.