Others' Island (spoilers all books incl RWC)

[Nuytsia]

Umm here I go again being picky, but could you pop a note as to what the spoiler is for.... I don't know if I'm asking for more than is generally required.... if so just ignore me!
It's just that I clicked it thinking oh it's probably something I already know seeing I've read every book except one..... and it turned out to be the one I haven't read! (unless I've REALLY missed something in Dragon Keeper..!!)

Wish I had some wisdom to share on what those beach treasures mean though!