Princess Diana angered the Queen by wearing this heirloom wrong, royal expert claims

• Princess Diana angered Her Majesty the Queen by wearing a family heirloom necklace as a headband, according to a royal expert.
• The Princess of Wales can be seen wearing the emerald jewellery across her forehead as she attended a gala dinner in Melbourne, Australia back in 1985.
• In other royal news, Prince Charles gives up beloved home ahead of becoming king

Princess Diana angered the Queen, it's claimed, by wearing a family heirloom necklace as a headband.

When it comes to setting fashion trends, Princess Diana took the lead in the royal family but one particular choice of accessories is said to have not gone down well with her majesty, Queen Elizabeth II. 

Rule breaker Diana has previously chosen to push the boundaries when it comes to royal attire - from the ‘revenge dress’ to opting not to wear gloves on official visits - it's no secret that Diana did it her way when it came to royal dressing.

But in 1985, the Princess is said to have overstepped the mark when she chose to use a royal family heirloom necklace as a headband when she attended a gala dinner in Melbourne, Australia, with then-husband Prince Charles. 

READ MORE: How did Princess Diana and Prince Charles actually meet?

Why did the Princess Diana headband cause a stir?

Well, Diana paired a teal satin evening gown made by her wedding dress designers David and Elizabeth Emanuel with the heirloom piece of jewellery - notably an art deco, emerald choker, once belonging to Queen Mary.

The princess had been gifted the precious item by the Queen upon her joining the royal family.

‘What Diana was wearing while dancing around in her husband’s arms was actually a necklace that was part of the Crown Jewels that she had been given by Queen Elizabeth herself,’ royal commentator Debora Attanasio told Marie Claire Italia.

Diana went on to wear the choker as it was intended, around her neck.

READ MORE: The heartbreaking reason the Queen and Prince Philip don't live together

"It was a piece that the Queen was very fond of, but which she, in turn, decided to pass on to Diana as a wedding gift," Attansio said.

"According to sources close to the Queen, having seen what Diana had done with it, Her Majesty became very irritated."

And if you're wondering what pushed Diana into the bold move, Royal biographer Kitty Kelley claimed in her book The Royals that in a rush, Diana tried to put the choker over her head, rather than wait for someone to help her clasp it. When it got stuck and wouldn’t go over her nose, Canadian diplomat Victor Chapman convinced her to wear it as a headpiece instead.

‘Diana took the necklace and put it over her head rather than wait to have it clasped around her neck. She couldn’t get it over the bridge of her nose,’ Kelley wrote. ‘Vic roared. “Leave it there,” he said, “It’s young and fun, like you”.’