Longreach Group, the buyout firm founded by former UBS Group AG investment banker Mark Chiba, is considering an initial public offering of its jewelry business Primo Japan Inc., people familiar with the matter said.

The owner has been working with Nomura Holdings Inc. to explore options that could also include a sale of the Tokyo-based diamond ring seller, the people said. Any deal could value the business at more than $200 million, said the people, who asked not to be identified because the details are private.

Primo, which makes and sells semicustomized bridal jewelry, has been expanding outside its Japanese market. Last month, it opened its first store in Beijing, and eighth in China, located on the capital's popular Wangfujing shopping street, its website shows.

Established in Japan two decades ago, Primo now has about 111 stores in Asia, including locations in Taiwan and Hong Kong. Longreach bought Primo in 2015 from a Baring Private Equity Asia affiliate, the buyout firm's website shows.

While an IPO is currently the preferred option, Longreach could still opt to sell the business to another private equity firm or a rival retailer, the people said. Deliberations are at an early stage and no final decisions have been made about a sale, they said.

A representative for Longreach couldn't be reached for comment, while representatives for Nomura and Primo declined to comment.