At the World’s Fair of Money, you can see a penny worth $1,000,000

"You literally can see one billion dollars and it won't cost a cent," said Donn Pearlman, spokesman and former board member at the American Numismatic Association.

He was referring to the forthcoming World's Fair of Money, the association's annual convention, which will be held this year at the Convention Center starting Tuesday, Aug. 14. The gathering is "an opportunity for our members and the general public to see a lot of coins they could never see otherwise … plus, an opportunity to see some of the largest, most successful [coin] dealers in the country," said Douglas Mudd, curator and director of the American Numismatic Association's Money Museum in Colorado Springs, Colo.

In addition to looking over rare coins on display, visitors will have the opportunity to walk the "Mint Promenade" and see booths from mints around the world and displays from seasoned collectors, as well as attend talks. Kids (and adults) will have the chance to play the "Prize Drop" game to earn prizes, or step into a Cash Cube and grab for bills.

But perhaps the coolest thing to see for casual coin aficionados is the exhibit that will feature millions of dollars worth of rare coins with face values of less than a buck. This showcase will be in the back of the Convention Center, next to the Kids Zone and concession stand.

One of the coins on display tells the story of Philadelphia's contribution to the war effort during World War II. In 1943, the U.S. Mint stopped producing pennies made of a bronze alloy that included copper and began producing pennies made of zinc-coated steel in order to preserve the copper for military use. However, a few bronze alloy planchets — bronze discs before they're struck with the markings of a penny — were left. They were made into some of the only 1943 Lincoln cents made of bronze, relics of prewar prosperity. The penny that will be on display sold for more than $1 million in January, making the World's Fair of Money a chance to see a coin worth 100,000,000 times its original value.

The million-dollar penny is not the only coin that will have a homecoming — Philadelphia is the home to the country's first mint, where many of the exhibition's rare coins were made.

There are coins worth even more than the penny. The 1913 liberty head nickel, which Pearlman described as "America's most famous rare coin," is insured for $3 million, its estimated market value. It was struck during what Mudd describes as "a dark and stormy night at the mint," where someone made the coins using the old design with Lady Liberty rather than the new nickel design for that year. Only five were minted. The coin rose to fame when a rare-coin dealer, Samuel W. Brown, advertised that he would pay $500 for one in 1919, even though he already owned the entire set. Mudd said that at the time, trolley cars often ran late because conductors would stop to search for liberty heads in the change they collected.

The world's first decimal coinage system, thought of as the "first draft" of U.S. currency, will also be on display, as well as some of the original paper banknotes Benjamin Franklin produced. "Money is history you can hold in your hands," said Pearlman.