The Royal Family had been out in full drive on Monday for the Garter Day procession, a commemoration of the Order of the Garter held at Windsor Carter. As Kate will not be a member of the Order, she was pictured on the sidelines watching her fellow royals and husband Prince William participate within the show of pomp and pageantry. For the high-profile royal occasion, Kate wore an on-brand basic blue outfit with some actually expensive jewelry to match.

The earrings and necklace Kate wore for the service on Monday function tanzanite, a uncommon stone discovered solely in Tanzania, adorned with some further sparkle.

Zack Stone, Managing Director at Steven Stone, stated: “What’s particularly impressive about Kate’s pendant is that it features 20 round brilliant cut diamonds – this means that they’ve been cut in a particular way and have many facets, imparting a look of exceptional brilliance.”

Royal fans may have spotted the similarities between Kate’s necklace and earring set and the iconic sapphire engagement ring she is rarely pictured without.

Mr Stone added: “Despite featuring a different gemstone – tanzanite – the set perfectly compliments Kate’s engagement ring, which features a deep, royal blue sapphire.

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“Not only is tanzanite one of the world’s most recently discovered gemstones but it’s also only mined in one place, making it one of the rarest.”

The stunning set was made by G. Collins and Sons, and the gemstones are set in platinum.

As one might imagine for one of the rarest gemstones in the world, Kate’s tanzanite jewellery could expect to be sold for a significant price.

Mr Stone added: “I’d estimate the combined value of the set to be around £30,000.”

The earrings had been famously worn by Diana on the 1996 Met Gala, they usually completely match the enduring sparkler.

Kate has additionally borrowed some iconic blue items from the jewelry assortment of her grandmother-in-law, the Queen.

The Duchess definitely had the Queen’s seal of approval for her Christmas carol live performance final yr, because the monarch lent her a pair of sapphire and diamond fringed earrings for the event.

During a go to to Scotland final yr, Kate additionally had the honour of sporting the Queen’s Dubai sapphire earrings.