A trio of Coca-Cola illustrations by Norman Rockwell have been put on the Most Wanted list and the bounty is worth about $1.5 million.

After searching on its own for decades, the Atlanta-based beverage giant has teamed up with “Antiques Roadshow” to track down the paintings, created by the famous illustrator in the 1930s for the company’s calendars and billboards.

The artwork, which depicts Americans enjoying the popular soft drink, have been valued by one appraiser at up to $500,000 each.

“Norman Rockwell is the quintessential illustrator,” said Ted Ryan, a spokesman for Coke's archives, who described the paintings as the biggest missing pieces of the company’s extensive collection of memorabilia.

“This is right on par with the [Haddon] Sunblom's pieces,” Ryan said of the famous series of paintings of a Coke-drinking Santa Claus, which many say is the basis of the modern day depiction of Saint Nick.

The lost Rockwell pieces will be part of “Antiques Roadshow's” Most Wanted segment, which focuses on everything from stolen art sought by police to furnishings that seem to have vanished into thin air.

Adam Monahan, an associate producer for “Antiques Roadshow,” said initially the program, which shot the episode back in August, had visited Coke to give a behind-the-scenes look at the company’s archives for Coca-Cola collectors.

But after talking with Coke officials about the paintings, the program’s leaders seized the opportunity to pair their Most Wanted segment with one of the most well-known brands in the world, he said.

“We thought that might make for a very exciting story that I don’t think a lot of people out there know about,” Monahan said.

Ryan said Rockwell actually created six illustrations for Coke, four for calendars and two for billboards. Three were recovered over the years, two of which hang at the World of Coca-Cola. The third is in the office of Coke Chief Executive Officer Muhtar Kent.

At the time of their creation, illustrations, especially those that were used for advertising, were not considered high art. Often the original artwork was discarded or given away after it had been photographed for its intended purpose.

Rockwell's stature persuaded Coke to allow him to keep his signature on his work, even when repurposed for calendars, posters or ads, a deal not enjoyed by any other artist who worked with the company, Ryan said.

Ryan and archive head Phil Mooney have since looked nationwide for the missing pieces, including private collections, auctions and at the Normal Rockwell Museum in Massachusetts and the American Illustrator Museum in Rhode Island.

“These paintings have been the top of the list for us as long as I have been here and that’s been about 15 years,” Ryan said.

Monahan said whoever has one of the paintings -- or all three -- is sitting on a pot of gold.

“The interesting thing is that there is someone out there with a winning lottery ticket,” he said.

Television preview

Antiques Roadshow, 8 p.m. Monday, on GPB

Coke has created a special blog post where readers and viewers of the program can submit leads on the missing paintings. It goes live April 23 at http://www.coca-colaconversations.com/my_weblog/2012/04/antiques-roadshow-and-the-missing-coca-cola-rockwell-paintings.html