Maybe It's Peppermint Madness

Working at the Poles can make you a little nuts. And it has nothing to do with Global Warming.

Working for long periods in the harsh and unforgiving conditions near the North and South Poles often causes people to suffer a stew of psychological symptoms
dubbed "polar madness," scientists said on Wednesday.

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Gives some insight into dear Yukon Cornelius, whom I discovered was actually mining for Peppermint. Not Silver and Gold. Makes a little more sense as he kept licking the end of this pick axe.

from Wikipedia:
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The removal of the scene near the end of the special (for subsequent
telecasts) in which Yukon Cornelius discovers a "peppermint mine" by that method near Santa's workshop left audiences assuming that he was attempting to find either silver or gold by taste alone. The scene was returned to the
(Rudolph )film in 1998 as well.