Whether it’s a ball or a special event, the Queen and Kate Middleton will reserve their best family jewels for these formal events.
The Duchess Of Cambridge is often seen wearing jewels lent to her from Her Majesty – something that Meghan Markle will have to wait for until she married Prince Harry in May 2018.
And there is a very special reason why the royal women wear jewels for occasions such as these, and it’s not to show how rich they are.
In fact, it’s to show that they are taken women, and are no longer on the market.
A senior tutor for The English Manner etiquette consultancy, Diana Mather explained to the BBC that jewellery, such as tiaras, are reserved for married women or members of the Royal Family.
She revealed: “The old rule is that hats are never worn indoors after 6pm, because that is when the ladies changed into evening dress, and tiaras and the family jewels would come out.
“Flashy diamonds and tiaras are not worn during the day, and only married ladies wear tiaras.”
Mr Harrold, an etiquette expert, known as The Royal Butler, added: “For married ladies it was a sign of status and would show you were taken and not looking for a husband.
“For the gentleman it was a clear sign not to make advances toward the lady in question.”
In other words, if you ever happen to be at a royal event and someone is head-to-toe in diamonds, don’t bother chatting them up.
In other royal news, more intimate details from Prince Harry and Meghan Markle’s May wedding have been revealed – see them here.