Hen that lays golden eggs
A hen or chicken laying golden eggs for its owner.
The idea of such a magical chicken has been encountered in several fairy tales such as Jack and the Beanstalk as well as the occult with the story of The Black Pullet - teaching an individual how to create such a creature through talismanic magic.
Perhaps the most interesting mystical aspect described in the book is the power to produce the Black Pullet, otherwise known as the Hen that lays Golden Eggs.
There have also been references to other animals that produce golden eggs or are of a golden nature, such as Aesop's fable The Goose that Laid the Golden Eggs, the Brothers Grimm fairy tale The Golden Goose, and in cinematics, Willy Wonka & the Chocolate Factory.
It is also an expression which relates to Alchemy (a philosophy and a practice with an aim of achieving ultimate wisdom as well as immortality) referring to the ideal of gaining pure gold from nothing through magical means. For example a person who has suddenly come into a lot of money is said to have a "hen that lays golden eggs".