In the past few years, pearls’ opalescent glow has been making appearances on some very stylish people, including the red-carpet stylist Kate Young, the art dealer Sarah Hoover and the rapper A$AP Rocky, who piles on strands of pearls in a way that recalls the opulence of the Indian maharajahs.

The “Kate-effect” and the “Meghan-effect”—that is, the instant sell out of whatever these relentlessly photographed royals wear—has been well-documented. When it comes to their jewelry, which skews very traditional, emulation is trickier. Most of us can’t spring for a tiara or diamond brooch, but a pearl pendant or earrings, even if fake, comes close. If nothing else about your outfit says “I’m going to cut the ribbon at a hospital opening,” pearls, long associated with modesty and good taste, add an element of faultlessness that reads as royal-ish.

Of course, not everyone who wears pearls wants to look like a royal. An ’80s jewelry revival, for instance, has begot big chunky pearl necklaces unsuitable for ribbon cuttings. Other factors pushing pearls of all varieties to the forefront of fashion include influential designers like Phoebe Philo, whose baroque pearl earrings for Celine (when it was Céline) have become even more in-demand since she left the brand earlier this year; Miuccia Prada, who’s made pearls part of the vocabulary of Miu Miu; and Simone Rocha, for whom the pearl has become something a professional emblem.

Younger women are definitely driving the pearl resurgence. As the owner and creative director of fine jewelry brand Sidney Garber, Brooke Garber Neidich is renowned for her pearl designs—such as the large pearl drop earrings that Mary-Kate Olsen wore to the Met Gala in 2014—and has observed at close hand the interest that younger women have in the gems. “My daughter, who doesn’t wear makeup and doesn’t put anything in her hair—she wears pearl earrings,” she said. “I was married in pearl earrings that belonged to my mother. My hip daughter-in-law with tattoos was married in the same earrings.”

Kentaro Nishimura, the chief operating officer of Mikimoto America, a subsidiary of the Tokyo company, said that sales of traditional pearl necklaces have been strong, but that what really interests younger customers are “smaller pieces like rings and pendants,” which tend to be less expensive. Male customers, he said, are buying black pearls in the form of bracelets and necklaces.

It’s worth noting these sales trends at Mikimoto because it’s the company that first put pearls within the reach of the non-wealthy consumer by perfecting the cultured pearl process in the 1890s. Before that, pearls were fabulously expensive because of their scarcity. Natural pearls remain rare: Only one in 10,000 oysters will produce one good enough for commercial use. When Ferdinand and Isabella of Spain agreed to finance Christopher Columbus’s journey to the New World, pearls nearly topped the list of goods they expected him to bring back; they knew that whoever controlled a fresh source stood to make a fortune. On his third voyage, in 1498, Columbus discovered rich pearl beds off the coast of what is now Venezuela. Pearls harvested from these beds, which were depleted in about 150 years, are visible in 16th and 17th century portraiture.

Johannes Vermeer’s 1665 canvas, “Girl With a Pearl Earring,” likely qualifies as the most famous pearl-related painting, but also interesting is Adriaen Becker’s “Regentesses of the Amsterdam Orphanage” from 1683, which depicts four women wearing double- and triple-strand necklaces that would not look out of place in a photo from the 1950s, another pearl-mad era, or on a female political figure of today.

Though royals are popularizing pearls again, the way true tastemakers wear them echoes Coco Chanel’s 1920s rejection of tasteful tradition. She chose instead to pile on both real and fake pearls and, as Christian Dior later remarked, “With a black pullover and 10 rows of pearls she revolutionized fashion.”

Today’s pearl disrupters, too, have little patience for conventions. Ms. Rocha, whose (fake) pearl hair clips are favored by cool girls like Alexa Chung, says that’s her preferred way to wear them. “It’s very classic but very playful and also practical. It’s unexpected,” she said.

Pearls, unexpected? What a welcome change.

HAVING A BALL / Surprising Designs That Rework Pearls

PHOTO: F. MARTIN RAMIN/THE WALL STREET JOURNAL

From natural pearls to stark settings, luster is letting loose. Clockwise from far left: Collar, $600, sophiebuhai.com; Hair Clip, $25, reliquiajewellery.com; Earrings, $9,000, sidneygarber.com; Hirotaka Earring, $195, barneys.com; Mules, $1,725, jimmychoo.com; Skirt, $3,990, oscardelarenta.com; Ring, $11,400, Chanel, 212-535-5828.