According to the Gemological Institute of America’s (GIA) report on the stone, the brilliant-cut ... Among them are a 8.2-carat blue sapphire ring, set to go for anywhere from $300,000-$500,000 ...

The Princess Royal's first engagement ring from her ex-husband Mark Phillips is front and centre in the striking portrait ...

Walsh pointed out that due its ties to Diana, Kate's ring is the priciest in the royal collection. "When you also consider ...