Queen Elizabeth may have been dressed casually for her surprise outing at the Windsor Horse Show on Friday, but she wasn't without her go-to beauty look.

The monarch, 96, watched from her Range Rover as her horse Balmoral Leia took first place — and her cheerful smile was highlighted by pink lipstick.

Last month, the Queen went for a drive around her Sandringham estate on her birthday also sporting a bold shade of lipstick.

While we don't know the exact shade, we do know that Queen Elizabeth's beauty stash includes Elizabeth Arden, a brand that has held a Royal Warrant for nearly 60 years, in part thanks to a close partnership with the monarch's senior dresser and in-house designer Angela Kelly. She's reportedly a fan of their Beautiful Color Moisturizing Lipstick, which comes in seven shades.

RELATED: Queen Elizabeth Is 'in Great Spirits' as She Makes Surprise Appearance at Windsor Horse Show

The makeup might also be from Clarins, which also has a Royal Warrant. The monarch is said to have commissioned the French beauty company to create a bespoke red lipstick for her to wear on her Coronation Day in 1953 — and it needed to have staying power, as the ceremony alone was three hours long!

In addition to knowing exactly what shade best suits her over the last seven decades, the Queen has also perfected the art of retouching without a mirror. She has been spotted through the years taking a lipstick from her handbag and reapplying after dinner or before leaving an event, despite the grandeur of the occasion.

Queen Elizabeth's visit to the Windsor Horse Show on Friday marked her first public outing since attending the Service of Thanksgiving honoring her late husband, Prince Philip, on March 29.

"She was in great spirits," an observer at the horse show tells PEOPLE. "People she knows in the horse world were being brought to her to talk to her at the window. You can see she is in really good form."

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Later in the morning, the Queen was driven to the main arena and was seen walking slowly to a lift, aided by a walking stick. She then made her way to her seat, which was next to her son Prince Edward in the stands.

And she got a special treat when her great-granddaughter Lady Louise Windsor rode by in the saddle of Prince Philip's carriage as she led a parade through the arena.