This mosque was built by the Sultan's father. Looks more shiny than the Sultan's mosque though. And it's right by the river, which makes it all the more picturistic.
This is the mosque built by the current Sultan of Brunei. And yes those domes are real 24K gold. In fact you'd be hard pressed to find something not made of gold inside.
But take note that this room is also incredibly cramped, stuffy and sometimes infested with insects too. It's not the holiday camp that it tries to make itself out to be sadly.