Pearls aren't something that I often wear and only very occasionally use in my own jewelry making. I was always horribly disappointed when I would see things that claimed that June's birthstone is the pearl. I've never particularly thought about why I have a distaste for them other than having always found them boring. That said, how they are created is sort of fascinating. The Guardian has an article up about an exhibit at the V&A that I wish I could go see about pearls though. The article is a fun read in refuting the "pearls start from a grain of sand" myth and detailing the more specific science of how pearls form out of excrement.
It sounds like there are some amazing pieces of historical importance as well as beauty on display for this exhibit.
The article is here.