As a 10-year-old in the 1950s Thomas Newman did what other boys his age did: he collected baseball cards.

Over a couple of years Newman assembled a treasured collection that was not equally prized by his mother, who thought of the cards as garbage and tossed them out. The loss inspired a decades-long passion to recoup what he'd lost. And then some.

"My dad began collecting in the early 1980s starting with baseball cards from 1957 and 1959 when he was ten to twelve years old," his son Stewart Newman said. "Those were replacements for the treasured cards of his youth that he kept in shoeboxes as a youngster and that his mom later threw out."

Eventually Newman, who died from COVID-19 in January, traveled the country piecing together an extensive stockpile of baseball and other sports memorabilia that auctioneers estimate is now worth about $20 million. And next month, they'll be up for auction via Memory Lane Auctions from June 21 through July 10.

The sale will include an mint-condition 1933 Babe Ruth card that could become the most expensive of all time. Memory Lane Auctions President JP Cohen described the "Sultan of Swat" card, one of four in the world, as "the finest known of its kind."

The iconic Goudey trading card, which bears the number 53, depicts Ruth wearing the New York Yankees's pinstripes, swinging a bat against a yellow background. It originally came with a stick of gum. Eighty-eight years later it received a Grade 9 rating from the Professional Sports Authentication service, meaning it is in mint condition and close to perfect, Barron's reported.

The record for the priciest sports card ever sold at auction was set by a 1952 Topps Mickey Mantle card. It sold for $5.2 million to actor and entrepreneur Rob Gough.

Newman's card is expected to fetch even more than that as prices for rare, historic items have exploded in the collectibles market, Cohen said.

The auction will also include Ruth's 1916 Sporting News rookie card as well as a near-perfect 1952 Mickey Mantle rookie card (Topps PSA 8) that is expected to sell for more than $1 million, according to Memory Lane. Those cards became highly sought after for their rarity after thousands were dumped into the Hudson River in 1960 after overproduction.

Memory Lane says other Newman's rare collectibles "include some of the finest known examples of other Hall of Fame players including Ty Cobb, Lou Gehrig, Honus Wagner, Ted Williams and Cy Young, as well as World Series program books dating back to 1903." In all, the firm will be offering more than 1,000 vintage and modern baseball, football and hockey trading cards and other sports memorabilia from Newman's estate

"No one enjoyed collecting more than Tom," said his widow, Nancy Newman.

"He jokingly called his cards his 'paper babies,' and spent almost every day attending to his collection in one way or another. It gave him such pleasure. The only reason he would ever sell a card was if he had acquired the same card in a higher grade."

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