This is why Princess Beatrice never wears a tiara

Many of us are just as interested in the royal family tiaras as we are the iconic royal wedding dresses. Meghan Markle's Cartier crown, which was part of the Royal collection, was an art deco bandeau of diamonds and valued at more than £2 million. Kate Middleton's scroll tiara from the Queen's collection featured 149 baguette-cut diamonds as well as 739 brilliant cut diamonds and was estimated to be worth between £750k and £1.2 million.

However, Princess Eugenie's tiara was the most expensive of them all. The 93.70 cts cabochon emerald tiara, which was hand made by Boucheron in 1919, was borrowed from her grandmother the Queen and was valued at a cool £10 million.

Since her wedding, Kate has worn a number of tiaras at special dinners and on official royal business. But why have we never seen Princess Beatrice wearing one?

Jewellery expert Geoffrey Munn told Town and Country: 'Any woman may wear one, but ancient tradition has it that they must be a bride or already married.

'The tiara has its roots in classical antiquity and was seen as an emblem of the loss of innocence to the crowning of love. One of the mainstays of European royalty and aristocracy is to do what you have always done and formal dress, jewellery, and tiaras are just part of this.

'Tiaras are certainly amongst the largest pieces of jewellery, and certainly the most imposing, but they not emblems of inherited rank. It is not the owner that triggers the wearing of tiaras but the event at which they are worn. In the past they were worn at full evening dress occasions, which are now know as "white tie."'

'Sometimes the invitation would say "Tiaras will be worn." This is virtually over now. Correct form decreed that they were never worn at hotels. That too has fallen by the wayside.'

So Princess Beatrice will likely have to wait until she gets married to wear a tiara.