Every once in a while, Kate Middleton and Meghan Markle bless royal fans by stepping out in jaw-dropping diamonds, usually borrowed from monarch Queen Elizabeth. But, like most everything with the British royal family, Kate and Meghan’s diamond-wearing moments come with one major protocol rule — they can’t be worn before 6 p.m. 

During a recent interview with News.Com.Au, etiquette expert Myka Meier revealed that royal women can’t wear diamonds during daytime hours unless it’s a “special occasion.” So why exactly is that a must-follow royal rule? Apparently, the 92-year-old Queen doesn’t want female members of the monarchy to appear too “flashy” in certain circumstances. 

kate middleton tiara
Getty Images

“Other jewels are worn pre-6 p.m. Before 6 p.m., you’ll see metallics, gemstones, pearls, [and] sapphires,” Meier explained. “At night, you’ll see the diamonds come out, and that’s in order to not come across as flashy in your appearance.”

Not surprisingly, the diamond rule is just one of many style protocol regluations Kate, 36, and Meghan, 37, must follow now that they’re a part of the royal family. According to Meier, the Duchesses also can’t wear open-toed shoes during some occasions, must wear pantyhose, and should always keep their shoulders covered. 

“They have a team who know what is appropriate for the event they’re attending, and Meghan especially would be given a lot of advice on [what to choose],” the expert shared. “During the day, when the Duchesses are on duty, we typically only see closed-toe shoes. We often don’t see too much of a platform for a day event, and we tend to see open toe only at red carpet events.”

meghan markle tiara
Getty Images

As for pantyhose, Meier explained, “It’s very traditional for female members to wear them. During the day it is something that’s seen as the most conservative, the most formal, the most professional in the role as a working royal.” And the no-shoulders rule? “At formal engagements, we typically always see the shoulders covered. So if [working royals] are going to a charity event or a walk through a hospital or museum, it’s expected shoulders will be covered,” she said. The more you know! 

Join our Facebook group for the latest updates on Kate Middleton, Prince William, and all things royal!