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Nails -

The women of the Royal Family do not wear vibrant nail polish.

Kate Middleton always sports a natural look or a light nail polish.

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Nails - Nail polish brand Essie revealed that Queen Elizabeth's hairdresser sent them a letter in 1980 requesting the light shade 'Ballet Slippers,' claiming it was the only one she wore.

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Gloves -

Royals are often seen wearing gloves during royal appointments.

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Gloves -

They shake hands with thousands of different people every day, so the gloves are also hygienic.

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Tiara - The tiaras worn by Kate are always hugely popular.

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Tiara -

Tiaras are reserved for the married women of members of the Royal Family.

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Colors -

Kate Middleton usually opts for vibrant outfits during her public appearances.

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Colors -

She picks strong-colored outfits so that people can identify her at events and among crowds.

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Hats - Hats and fascinators (headpieces) are traditional items that must be worn at formal day events, such as weddings and baptisms.

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Hats - The Princess of Wales doesn't always match her hat with her clothes.

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Hats - At official state dinners, the hat is replaced with the tiara.

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Skirts - Long skirts are preferred at formal events.

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Skirts - The length of the bottom clothing item is also chosen according to the culture of the country or place they're visiting.

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Skirts - But mini-skirts aren't accepted in the Royal Family dress code.

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Platform sandals - Heels are a whole other subject. Even though Kate has been seen wearing platform sandals, she has never worn them in front of the Queen.

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Platform sandals - According to Vanity Fair, a source close to the Royal Family said that Her Majesty simply wasn't a fan of these shoes.

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Heels - The best option is always the classic scarpin.

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Necklines - Necklines are not particularly welcomed by the Royal Family.

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Necklines - It is extremely rare to see Kate wearing any kind of neckline at official royal engagements.

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Necklines - Princess Diana's trick when getting out of the car was to cover her neckline with her purse.

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Colors -

The Royal Family members follow a specific color palette. When visiting a foreign country, they opt for colors that pay homage to the host nation.

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Colors - For instance, when the Princess visited Canada, she wore a white dress and a red fascinator, representing the colors of the Canadian flag.

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Colors -

Black is a color that is worn at times of mourning or, very rarely, at evening events.

See also: Who's next in the line of succession to the British throne?

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