[quote=@rush99999]
If you're open to suggestions how about this: The magical properties of the powdered gemstones that make up the sand, which were once in fact friendship gems, can let a dragon return a friendship gem to teleport to the dragon they are returning the friendship gem to.
[/quote]

Friendship gems aren't an in-game thing. They're merely an out-of-game way of keeping track of your bonds with other party members. However, this does give me an idea of something the sand [i]could[/i] be that has the same effect as you described.