Yukon Cornelius is the tetartagonist from the 1964 Rankin/Bass television special Rudolph the Red-Nosed Reindeer. He is an arctic prospector who meets Rudolph and Hermey while they are trying to avoid the Abominable Snowmonster. Seemingly searching for valuable minerals at the North Pole, his greedy behavior inspires the song "Silver and Gold", sung by Sam the Snowman. (Originally, Yukon was going to sing it himself before it was decided that the special should have a narrator.) Yukon accompanies the pair in their travels to the Island of Misfit Toys and back. He is a blustery but benign character and ends up helping not only Rudolph and Hermey, but later the Abominable Snowmonster, or "Bumble" as he refers to him, as well.
Throughout the special, Yukon is shown tossing his pick axe into the air, sniffing, and then licking the end that contacts the snow or ice. This leads the audience to believe that he is searching for either silver or gold, though it turns out that he is actually seeking peppermint, as revealed at the end of the original version of the special. The removal of the scene (for subsequent telecasts) in which he discovers a "peppermint mine" near Santa's workshop by that method left audiences assuming that he was attempting to find either silver or gold by taste alone. The scene was reinstated in the special in 1998.
Yukon oddly didn't reappear in Rudolph's Shiny New Year or Rudolph and Frosty's Christmas in July, but he did reappear in Rudolph the Red-Nosed Reindeer and the Island of Misfit Toys.