When did Pokemon Shiny Gold come out?

There is no official Pokemon game called "Shiny Gold." It seems like you might be referring to a fan-made ROM hack or a similar project.

To give you a more accurate answer, could you please tell me:

* What platform are you referring to? (Game Boy Color, Game Boy Advance, etc.)

* Is it a fan-made project or an official game?

* Do you have any more details about the game, like its title or any specific features?

Once I have more information, I can help you find out when it was released.