The ring, which is now the engagement ring of the Duchess of Cambridge, renewed a sales boom in sapphire and diamond rings in 2010 when the royal couple became engaged.
It features a stunning Sri Lankan 12ct cornflower blue oval faceted sapphire surrounded by 14 round brilliant cut diamonds, set in 18ct white gold.
It was made by royal jeweller Garrard & Co Limited and surprisingly wasn’t a custom made ring – meaning any member of the public could buy it.
The ring, now worn in memory of Prince William’s mother, was originally valued at £28,000 in 1981.
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But, it’s also hard to ignore that red often symbolises the colour of passion and love.
Like sapphires, rubies are a great choice for an engagement ring as they can weather everyday use.
Most modern day three stone rings would be set with a central coloured stone, such as a ruby, sapphire or emerald, shouldered by matching or graduated diamonds.
Here the combination has been inversed. It consisted of a central emerald cut diamond weighing approximately 1.5cts of a colourless grade and VVS clarity. Speculations put the cost of the diamond at £11,000.
Framed on either side of the diamond are two emerald cut rubies weighing roughly 0.75cts each.
They could have come from Brazil, where the Crown Prince was visiting before his engagement in 2003.
This is fairly uncommon, as rubies are most often mined in South or South-East Asia, or Africa.
It is also believed the ring was made there in Brazil, however, other sources believe the ring may have been part of Denmark’s Queen Ingrid’s collection, who passed away in 2000.
Either way, the rubies are of a deep vivid red colour and of strong saturation, standing out against the brilliance of the diamond.
Later on in 2012, Princess Mary supplemented her three stone ring with the addition of a further two baguette diamonds, each one weighing approximately 0.30cts.
The finished look produces a very elegant, graduated arc on the finger, adding to the presence of the already remarkable rubies and exquisite central diamond.
I would value the retail price of this ring to be about £30,000, but this could easily double should it ever be presented at auction.
Should you be looking to wear the colour of love like Princess Mary, this Chopard watch could be for you.