Green Lantern Fan Moved to Tears by Double Rainbow

Gfest is unsure how to exactly describe this clip.  We can only assume this is a Green Lantern fan who upon seeing the emotional spectrum of the rainbow was so moved that his emotions began pouring out of him.

I can only image how this guy reacted when he actually read Blackest Night.
Presumable there is a white lantern at the end of this rainbow.

Where Rainbows REALLY Come From

This shirt, available here, show the real story behind the origin of rainbows.  This leaves us with just one question.  What is REALLY in that Pot of Gold at the end of the rainbow?