When Mickey Mantle retired from baseball, he was a little bewildered at his celebrity status.

Once, at an auction where one of his old Yankee uniform shirts was being sold, he was astonished when it brought $50,000.

"Fifty thousand?" he said. "If I had known it was worth that much I'd be sleeping on it."

That was just after "The Mick" retired from the game in 1968.

That same shirt today would be priceless.

Baseball collectors long ago turned Mantle into a "cottage industry." He appeared frequently at sports card shows to sign autographs at $35 to $50 a signature.

The Hall of Famer's baseball cards are among the most prized of baseball memorabilia, with the majority of the cards bringing $300 to $1,000. His rookie card is valued at up to $30,000.

"Those prices will zoom now," said Ed Freeland, referring to one effect of the Yankee star's death last week.

Freeland, a card hobbyist who occasionally sets up at card shows, was one of a number of sports card dealers and collectors who were at Wild Bill's Sports Card Shows at the Show Me Center on the Southeast Missouri State University campus Saturday.

The twice-a-year show is conducted by Bill Foster, a sports card hobbyist. The next show is scheduled for Oct. 7 at the Show Me Center

Only a few Mantle cards along with some magazines featuring the slugger on the covers were to be found at Saturday's show

"A lot of people are looking for Mantle autographs now," said Freeland. "I don't think you'll be seeing any for awhile, though. The good Mantle memorabilia will be put back on shelves, waiting to see what will happen to prices since his death."

The 63-year old superstar died of liver cancer at Baylor University Medical Center in Dallas, Tex.

"I think Mantle will rank right up there with Babe Ruth and Joe DiMaggio collectibles," said Freeland. "The Mick could do it all -- hit, run, field the ball..."

Foster, an employee at Broadway Cards in Cape Girardeau, agrees.

"I don't have any Mantle memorabilia," he said. "But I try to keep up with the card hobby. That's my livelihood."

Foster, like other sports card enthusiasts, is happy to see interest redeveloping in baseball cards.

"The interest really sagged last year during the strike," said Foster. "And, sports fans are just beginning to renew their baseball card interest."

"We had a big letdown in baseball cards," agrees Edwin Shumate, a sports card dealer who displays his baseball memorabilia in Missouri and Illinois shows, including Wild Bill's show.

Shumate and Foster agree, however, that the letdown in baseball cards put football and basketball into the spotlight.

Shumate expects the Mantle items to double immediately. "Mantle was a great player," he said. "He was one of the greatest."

David Wright, a baseball collector from Anna, Ill., agrees.

"Mantle memorabilia prices will go up," said Wright. "Everybody will be looking for Mantle."

Wright, who was looking for Mantle items and other baseball memorabilia at Saturday's show, revealed a Mantle collectible he had acquired a year ago.

A Mantle/Griffey card was part of an Upper Deck Cards promotion, featuring pictures and signatures of Mantle and Ken Griffey Jr.

"This card is valued at $750 now, and will probably double," said Wright.

Mantle, who was a big fan of another superstar -- Stan Musial of the St. Louis Cardinals -- long before he ever played at Yankee Stadium, made his first appearance in the Yankees' home grounds in 1951, when he was being groomed to replace DiMaggio.

Two years later, Mantle slammed a tape-measure home run that landed so far away from Washington's Griffith Stadium that a Yankee official had it measured at 565 feet.

In 1956, Mantle won the American League Triple Crown with 52 home runs, 130 runs batted in, and a batting average of .353. Babe Ruth never won the triple crown. Neither did Joe D.

Mantle was plagued by injuries during his career, but in 1961 he and Roger Maris were chasing Ruth's record of 60 home runs in a single season. Maris ended the season with 61 homers, but Mantle was injured late in the season and finished with 54.

But the 1961 feat by the "M & M" boys led to a special baseball cards of Mantle and Maris, which appeared as an insert in a Life magazine.

That magazine, now valued at about $200, could quickly reach the $400 level.

Mantle retired from baseball following the 1968 season. But in his final game, he hit one out, his 536th career home run.