User blog comment:HephaestusThePrivateer/Pirates of the Caribbean: City of Gold/@comment-5120604-20120306214328/@comment-1984959-20120308112837

The Fountain was because of it being in Tim Powers' book...itself so the writers can see if they can get something made, which IMO worked great. :)

However, I will say I agree with your statement, I would like to see some original treasure in the next film. While we currently have rumors of where to go(whether it be the City of Gold or the mostly-rumored Atlantis adventure), I'd like to see them go after the treasure Angelica mentions at the end of OST:
 * "Treasure! There is a chest with jewels! Jewels with the power to rule the wind and tide!"

Ok, on one hand, it could be one of Angelica's lies to get off the island(like Angelica being pregnant). But then again, she has been known to lie by telling the truth...so this treasure may have a likelihood of being true. ;)