Why did royal British coin fetch a record £430,000?

A British coin sold at auction for a record-breaking £430,000, at Baldwin's auctioneers in London. After fees, the buyer will pay £516,000. This makes it the most expensive modern coin minted in the UK ever to be sold.

So what's so special about it, and how does it compare to the most expensive coins of all time?%VIRTUAL-SkimlinksPromo%