The Golden Goose was the titular artifact and main plot element of the two part series finale of DuckTales, "The Golden Goose".
Found on top of a fountain in India, the Goose had the ability to transform anything (or anyone) into gold. But it would only work if the user said the word "gold".
The Brotherhood of the Goose protected it to keep it from falling into the wrong hands lest the Golden Goose come alive and its power to turn things into gold would spread unchecked, turning the entire world and every living thing in it to gold as well.
Dijon would steal it disguising himself as a tourist, it ended up in Scrooge McDuck's hands but then stolen by the Beagle Boys who first use it to turn the nephews into lifeless golden statues.
Later, the goose springs to life and goes on a wild frenzy turning objects and people into gold on its own.
Scrooge returned it to the fountain just mere seconds before the golden death covered the world (he himself was turned into gold when he was just at the fountain and only the fountain was spared the effect)