Pale Ore

  

Pale Ore is a material used in the creation of high-quality weapons. Providing the Nailsmith with Pale Ore will allow him to upgrade the Hollow Knight's nail. The first upgrade requires no Pale Ore, the second requires one, the third requires two, and the final upgrade requires three Pale Ore, for a total of six.

Locations
There are six pieces of Pale Ore to be found in total:

Bugs

 * Due to a known glitch, the Colosseum of Fools does not yield the correct rewards in the GOG version of the game, making the last Pale Ore unobtainable and the Pure Nail unavailable.