The Hong Kong designer Dickson Yewn has been preparing for an exhibition and sale in what, until a few years ago, would have been considered an unusual setting. The group show, curated by Vogue Italia, is scheduled at Christies auction house in New York rather than a downtown gallery or glitzy boutique.The Protagonist, scheduled Dec. 10 to 13, is to include Mr. Yewns bangles of reclaimed wood accented with diamonds as well as ceramic and diamond versions of his signature rectangular rings. Also on display: creations with emeralds and wild tagua seeds by Alexandra Mor of New York, the shows creative director; sustainably farmed pearls from the New York-based designer Ana-Katarina Vinkler-Petrovic and a white topaz ring with other gemstones by the Italian jeweler Alessio Boschi.Auction houses have held such contemporary art jewelry exhibitions and sales since the late 1990s. But, as they mine new methods of reaching clients and scale their efforts to welcome larger groups of potential buyers, what previously might have been private appointments or intimate dinners now are being mounted as public events.Sothebys, for example, has sold contemporary jewelry like Hemmerle earrings or diamond necklaces from Stephen Webster for more than 10 years. But Laurence Nicolas, the houses global managing director of jewelry and watches, wrote in an email that we had a number of high profile sales and exhibitions recently which put the emphasis on this aspect of our business, such as staging a sale in coordination with the houses design and contemporary art departments in January in Geneva. It also has scheduled one at the same time as its retail boutique, called Sothebys Diamonds, to begin Nov. 30 in London.Ms. Nicolas said it was the December 2017 sale of Shaun Leanes personal archives, including the jewelers collaborations with Alexander McQueen, that really was a watershed moment for the auction house.Other auction houses, like Artcurial in Paris, have pursued links with contemporary jewelers but are not going so far as to sell their work in exhibitions. To have regular sales exhibitions, you have to have the capacity of clients to pay, said Franois Tajan, Artcurials deputy chairman, noting that Monte Carlo with its rich international crowd would be a better location for such events than Paris.But Artcurial did have the Parisian jeweler Elie Top curate a fine jewelry sale in July 2016. And Mr. Tajan said the house would like to have two or three contemporary jewelry exhibitions a year, each for two to four days.We would be happy to promote other people separately not involved in the auction market. We would like to have three Elie Tops every year, he said.The financial side is at the center of the system, Mr. Tajan said, but with selling exhibitions or presentations like we did with Elie, the financial side is not the target. Its just a question of image.Image, yes, but also attracting new customers.Earlier this year Phillips scheduled its first contemporary jewelry exhibition sales. Susan Abeles, head of jewelry in the Americas at Phillips auction house, said the events, which featured Lauren Adriana, a London-based jewelry maker, and Ana Khouri, a Brazilian designer who works in New York, attracted visitors 30 to 50 years old who may not have known us before.The shows drew more women than usual, and Ms. Khouris show was on the ground floor of the auction houses New York space so it attracted more passers-by. We are increasing our notoriety, Ms. Abeles said.Forging connections with art jewelry makers also reflects a long-term commercial imperative: We have to widen the net from heritage jewelry, said Julie Valade, associate director of jewelry at Artcurial, because to find jewelry is increasingly difficult because we cant sell jewels from retailers. Weve got to get them from someone.And as David Warren, Christies senior international director of jewelry, said, there now are more auction houses, with more locations including in newly developing regions, like Southeast Asia vying for stock and for customers. As a result, competition for both have been increasing and pieces have been spread more thinly, he said.However, Louisa Guinness, founder of her eponymous contemporary jewelry gallery in the Mayfair section of London, said she is optimistic about the effects of auction houses exhibiting todays designers even though work by Eliane Fattal, one of the designers in Ms. Guinnesss current group show, Things That I Love, (to Dec. 21) also has been showcased at Sothebys.They are just helping with the marketing of these jewelers, Ms. Guinness said in an email. The more people interested in jewelry and original design, the better for me and my gallery. If they can help the market grow, my gallery and my artists will benefit.And, the better we do, Ms. Guinness added, the more younger designers we can support and that is only a good thing.Jewelry designers themselves say that, for the most part, they also benefit from the auction house sales.As Daria de Koning, a Los Angeles designer whose handmade one-off creations also are to be displayed in the Protagonist show at Christies, said, There are very few retailers that are taking a gamble on artist designers or they dont have that clientele or they dont understand artist jewelry.And for jewelers, like Mr. Yewn, who has his own boutique in the upscale Landmark Atrium shopping mall in Hong Kong, auction house events offer a different kind of opportunity than a shop or even art fairs. In the boutique, he said, you sell to unknown people who walk in randomly, whereas private sales-led exhibitions are targeted and you have to know the customer.(Although, he added, the designers dont get to develop relationships with auction house clients. I dont get to know customers of Christies and Im not supposed to ask for contacts, he said of the solo exhibitions he has done at Christies in London and Singapore).Designers have to pay for their participation, as well. The Protagonist show is charging each designer $7,500, and there will be shipping costs. Ms. de Koning said she expects to pay a little less than $10,000 in all for the event. Its a calculated gamble, she said.In the end though, Mr. Warren of Christies said, an increase in exhibitions selling contemporary jewelry is fueled by demand. Were selling contemporary jewelry because people like it, he said, and if there is a demand we want to be supplying it.