Julian Leidman, 65, operates Bonanza Coins in Silver Spring. He has been collecting coins since he was 11. In 2009, during a return trip toMaryland from a coin show in Connecticut, Leidman was robbed of more than 2,000 vintage coins and bank notes. (Jabin Botsford/FOR THE WASHINGTON POST)

As Julian Leidman packed up more than $4 million in rare coins after a Connecticut show, the thieves probably already had the prominent collector under surveillance and had laid plans for one of the biggest coin heists in U.S. history.

Leidman eased his minivan onto Interstate 95 south toward his Maryland home and the thieves probably followed, waiting and watching for dozens of miles. Then they saw their opening.

When Leidman stopped for dinner at Tiffany’s restaurant in Pine Brook, N.J., he took a table near a window so he could keep an eye on his vehicle. The thieves sneaked around the side he couldn’t see, smashed a window and took at least five cases.

Most of Leidman’s inventory was gone, more than 2,000 vintage coins and banknotes including one of the coin world’s major prizes — a 1921 Saint-Gaudens $20 gold piece worth as much as a modest home in the suburbs.

Thefts of rare coins have spiked in recent years, experts say, crimes linked to the run-up in gold and silver prices. Coin thieves are often part of organized rings, some from Colombia and others with ties to the Russian mafia, that orchestrate sophisticated, lightning-quick and sometimes ruthlessly violent heists, according to the Numismatic Crime Information Center, a nonprofit organization that tracks coin thefts.

Fairfax County police think thieves probably followed a dealer to his Annandale home after a show in April and snatched coins and banknotes worth as much as $500,000 when the dealer left his car for about 10 minutes. In 2011, a mother and son from Texas were convicted of being part of a scheme to steal $152,000 in coins from a New Market, Va., collector.

“Why rob a bank with cameras, witnesses, and there’s a good chance your picture will end up on the evening news?” said Steve Ellsworth, president of the Virginia Numismatic Society and a coin security expert. “Coin thefts often don’t have witnesses, and criminals can make off with far more money.”

The October 2009 scheme targeting Leidman, which has resulted in a case that is nearing its conclusion in federal court in New York, opens a window on the world of thefts that sometimes seems pulled from a Hollywood script.

Leidman, 65, has been collecting since age 11. His Silver Spring store, Bonanza Coins, is overflowing with boxes, buckets and glass cases full of coins. Leidman is a major player in the coin world, and the illustration of the $20 1907 Indian Head double eagle piece on one wall is a reminder.

Leidman bought the coin — there is only one — for $500,000 in 1979, making it the world’s most expensive coin at the time. He hoped to turn a profit on it, but the market soured and he unloaded it two years later at a loss. It is now worth an estimated $15 million.

Leidman jokes about his bad timing but grows serious when he talks about the theft. He spent four decades building his business, but in the space of a Sunday evening dinner it appeared to be falling apart. His insurance company did not cover the cost of the stolen coins, Leidman said. Some of the coins were his, while others he was selling on commission for other collectors.

“I was facing bankruptcy,” Leidman said.

He could have faced worse. In 2011, two masked men attacked a Houston area coin dealer at his home, according to the NCIC.

The thieves beat the man, tied him up and then bit him when he fought back, the center reported. To remove any DNA evidence from the wound, the suspects sliced around the bite and poured alcohol in it.

The men then put a gun to the head of the dealer’s daughter until he revealed the location of more than $500,000 in coins and jewelry, which they stole, according to the NCIC. No arrests have been made in the case.

The same year, a Brooklyn coin dealer was ambushed, robbed and killed. And in February, robbers slit the throat of a dealer and two other people before taking $500,000 in coins from his Louisiana home, the NCIC reported. Arrests have been made in both cases.

After Leidman was robbed, the coin world rallied around him, cobbling together a reward of about $160,000. As a New Jersey detective worked leads, Leidman agonized for more than two weeks — until he answered the phone one day.

“ ‘I think I was offered your coins,’ ” Leidman recalled a coin dealer telling him. “I wasn’t sure they were mine. Then he mentions a cheap Lincoln penny. At that point, I knew.”

Leidman said he called authorities — the trail led to New York City. The New Jersey detective, the FBI and other agencies tried to organize an undercover buy to catch the man selling the coins, but the plan fell though, court documents show.

They ended up simply visiting his shop: Albert & Sons, a major Manhattan cash-for-gold buyer that had been featured in a “Good Morning America” television segment.

During an interview with investigators, Yan Kandinov, the son of the proprietor, admitted that he knew about the stolen coins and said he had been offered them by a third party, court record show. The person had visited Albert & Sons and said he or she had “something for Kandinov to look at,” according to the records.

Kandinov met the person in Queens before they traveled to a house where the person showed him coins and banknotes, according to court records. Kandinov agreed to pay $80,000 in cash for the collection.

When authorities visited Kandinov, he agreed to turn over the collection. The items were still in Bonanza Coin slips, court records show.

Leidman said he went through the collection and determined that about 90 percent of it was there. Some important pieces, including the $160,000 1921 Saint-Gaudens $20 gold piece, were not. The missing items were worth hundreds of thousands of dollars.

Armed with a search warrant, authorities went back to Kandinov, who later turned over additional coins that were stashed in the ceiling of the store, court papers say. Leidman said the Saint-Gaudens piece was among them. Kandinov pleaded guilty to receiving stolen goods and is awaiting sentencing.

Leidman was lucky, in a way. The FBI reports that only about 4 percent of stolen precious metals and jewelry are recovered each year.

Doug Davis, president of the NCIC, said the boom in cash-for-gold buyers is helping drive the increase in coin thefts — and precious-metal thefts in general. Unscrupulous dealers provide a quick and easy fence for thieves, and the high prices for gold and silver have made such crimes more appealing. Some jurisdictions have begun imposing new regulations on buyers to combat the problem.

Still, the thieves are difficult to catch. Coins are hard to trace and easily melted down. Davis said most law enforcement officers know little about the world of coin collecting.

A central mystery of Leidman’s case remains: Who broke into the minivan? Kandinov is the only arrest and authorities declined to speak about the case. Kandinov and his lawyer also declined to comment. Leidman is in an uncomfortable position.

“I won’t have full closure until thieves are caught and convicted, but I have 90 percent closure,” he said, referring to the recovered coins.