In 1918, when he was 7, Eric P. Newman's grandfather gave him a strange old penny.

In the nearly 10 decades since, the passion for coin collecting ignited by that gift turned Mr. Newman into one of the hobby's most respected figures and a leading authority on the art and history of American money. Beginning last year, Mr. Newman - who, at 102, is still researching and writing on the hobby - began selling some of the prized items from his collection to benefit a foundation he established to promote scholarship on coins.

"He belongs to that tradition which barely exists today," said Ute Wartenberg, the executive director of the American Numismatic Society in New York, comparing Mr. Newman's trove to the old-time cabinets of storied collectors like J. P. Morgan.

The penny that started it all for Mr. Newman was a copper-nickel Indian Head cent minted in 1859, when the government was experimenting with different metals before settling on bronze. In due course, he would find other pennies, with different dates, in his change.

"This fascinated me," Mr. Newman wrote in an email last year. He began taking a streetcar to a coin store in downtown St. Louis.

"The round trip student fare was 3 cents. My allowance was 5 cents per week. I had to save enough to go downtown to buy a coin or so," he recalled.

The owner of that coin store was a man named Burdette G. Johnson. "On one visit to his store he refused to sell me the coin I selected because I knew nothing about it," recalled Mr. Newman.

"But if I would take home a book he would lend me and recite the coin's history on my next visit, he would sell it to me." This became a habit, with the coin dealer mentoring the young Mr. Newman as his knowledge grew.

"The key thing about Mr. Newman is the breadth of his knowledge," Ms. Wartenberg said. "He is not only a collector but a writer." He has more than 100 books and articles to his credit, and he has been awarded the highest honor among academic numismatists, which is rare for a collector.

Among Mr. Newman's other great acquisitions was a collection of Colonial paper money, whose owner sold it to him in the 1950s "to encourage me to write an all-encompassing book on early American paper money, which I eventually did."

"The Early Paper Money of America" was first published in 1967 and is considered one of the definitive works on the subject. Mr. Newman is working on its sixth edition.

Explaining his attraction to coins, Mr. Newman said they offered a "wonderful window into history and other fields for me. Numismatics involves economics, politics, geography, metallurgy and art."

"Many collectors can tell you some of the narrative behind their coins," Ms. Wartenberg said. "But Eric discovered the narrative."

To read the complete article, see:In Coins, Man Found a Century of Learning(www.nytimes.com/2014/05/19/us/in-coins-man-found-a-century-of-learning.html)