This aluminum egg is called a phi top, and when you spin it, it stands on end. According to the Action Lab Man, "This is the same procedure that [Nikola] Telsa applied to a copper egg in his famous Columbus egg demonstration."

If you don't have an aluminum egg on hand, an egg laid by a hen that has been hardboiled will do the trick. (In fact, this is a good way to determine if an egg is raw or boiled.)

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