Swanstone is or was a royal side in Erfworld, founded by Queen Meganite, formerly of Graceland. Prince Coal of Swanstone founded the side of Jetstone, becoming the first King of that Side. As such, Swanstone must have predated most of the Sides known to be in existance today, if not all of them.
- Queen Meganite - founded the Side, presumed dead due to extreme age
- Prince Coal - became King of his own Side, long dead
It is possible the side fielded Swan Knights.
The side is highly likely to be a real one and not purely the stuff of legends, as Jetstone is its immediate successor and has a similar name.
Real World References
It would seem there is a castle in Germany named 'Neuschwanstein Castle', which means 'New Swanstone Castle' in English. There is a company called Swanstone that specialises in stone kitchen and bathroom products.