This duchess is keeping it (semi) casual.

Meghan Markle went with a California cool look for a celebratory lunch with friends in a new photo shared by her pal Myka Harris on Instagram Tuesday, pairing a black tank top with a high-end gold pendant.

“Belated bday celebrations w/ these lovely muses,” the Instagram Story was captioned.

Markle wears Ariel Gordon’s Imperial Disc Pendant Necklace (price ranges from $1,840 to $2,555) in the pic, which can be engraved with a special name or phrase and is available plain or with two or three diamonds.

In the pic, the Duchess of Sussex, 42, drapes her arms around celebrity hair colorist Kadi Lee — who runs beauty and wellness brand Highbrow Hippie along with Harris — and poet Cleo Wade at an outdoor table as the three beam at the camera.

Celeb hairstylist Serge Normant, who styled the royal’s hair for her May 2018 wedding, was also tagged in the photo, with Harris adding, “missing sweet @sergenormant.”

Ariel Gordon Imperial Disc Pendant Necklace ($1,840 – $2,555)

Although it’s unclear what the mom of two’s pendant says, it does appear to have an engraving at the top along with small diamond.

The duchess went for a low-key makeup look for their outing, wearing her hair pulled back and clipping a pair of sunglasses on her top.

This isn’t the first appearance Markle has made on the Highbrow Hippie Instagram Account; in May, a photo of the royal and pal Kelly McKee Zajfen, co-founder of Alliance of Moms, invited fans to purchase T-shirts to support the charity.

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Lee — who works with stars like Julia Roberts — also shared a snap of the Duke and Duchess of Sussex when Markle was honored with the “Women of Vision” award, with the post sharing the secrets to achieving her “warm and rich brunette” color.

Although Tuesday’s post doesn’t state whose birthday the friends were celebrating, Markle turned 42 on August 4 and Lee celebrated her birthday at the end of July.

Along with their girls’ lunch, the Duchess of Sussex enjoyed a showing of “Barbie” for her b-day earlier this month and also stepped out with Prince Harry for a chic date night while wearing a striped tube dress by Posse ($240).

This Barbie knows how to accessorize.