When Garrett Ziss, 13, held the 200-year-old half-cent piece, he felt a direct link to the days when Baltimore’s Washington Monument rose on what was then the edge of the city.

His imagination came alive: Had President George Washington’s contemporaries held the same one? Had any of the holders fought in the War of 1812 in Baltimore’s harbor?

Sitting around a table inside the Maryland Historical Society, the young numismatist joined local historians to inspect and record details about two dozen coins and medals discovered two years ago in the monument’s two time capsules.

“These coins have been hidden away for 200 years,” said Garrett, of West Chester, Pa. “The last people who held these coins were probably people who knew George Washington.”

Uncovered during a massive renovation done for the Washington Monument’s bicentennial, the coins and medals were stuffed inside a pair of time capsules: the cornerstone buried when construction began in 1815 and a cooper box sealed behind a bronze plaque a hundred years later.

The older coins were wrapped individually in papers and placed inside glass jars. The newer ones were found inside an envelope.

They were taken down from an exhibit at the historical society so Garrett and three others could measure, weigh and photograph thepieces for a scholarly article they plan to write for coin collectors. They are back on display this week and will remain so until July.

Garrett first saw the exhibit when he and his parents visited Baltimore for a coin show in late 2015. During their stay, the family stopped by the historical society to view the original “Star-Spangled Banner” by Francis Scott Key, and stumbled on the exhibit featuring the contents of the time capsules.

The boy, whose interest in coins was sparked about six years ago during a math lesson about currency, wanted to find out more about them. So he wrote to local historians, including Lance Humphries, director of the Mount Vernon Place Conservancy. Humphries assembled the group after Garrett’s inquiry.

“We are just thrilled that the restoration really brought attention to this great history we have here,” said Humphries, who led the monument’s restoration. “Garrett’s interest in these coins pushed us to a whole other level of documenting everything we had in these two time capsules.”

Garrett said he was eager to see the reverse sides of the items, not visible when they were on display, to find out how rare they each were.

Early production of U.S. coins sometimes left unique or rare markings on the pieces, like signatures. Other coins contain errors. Because these sets were locked away in the time capsules for so long, Garrett said, examining them could determine what marking patterns were lost to time.

“I finally get to look at the reverse of all of the coins after a year and a half of suspense,” he said.

Garrett attends a virtual charter school outside of Philadelphia. He estimates that he is about 1 of 150 enthusiastic coin collectors, known as numismatists, around his age, based on his involvement in various groups. He has authored scholarly papers and makes presentations at coin conventions.

Last week, he joined a coin photographer, Humphries and Joel Orosz, a Kalamazoo, Mich.-based coin historian, to catalog the coin sets buried in Baltimore in 1815 and 1915.

Orosz called the time capsules’ contents “an extraordinary find” that also contain a few mysteries. The historians are going to research why the Baltimoreans who assembled the 1815 time capsule included a medal imprinted with a bust of the British Duke of Wellington as well as one imprinted with a bust of Washington.

They also want to know the extent of the involvement of the prominent Baltimorean Robert Gilmor Jr., considered one of the “founding fathers” of coin collecting, in assembling the earlier time capsule.

The 1815 coins, with a face value of $19.411/2, included all of the denominations minted at the time, including a half-cent, dime and a $5 gold coin, known as a half-eagle. Some could be worth more than a $1,000, but the values have not been determined.

The second batch had a total face value of $6.91, and included most of the denominations in circulation at the time with a silver dollar, nickle and half-dollar among the coins.

Some of the copper and silver coins were discolored from exposure and interaction with the papers they were wrapped in.

“This is what something looks like after 200 years in a cornerstone; they are truly one of a kind this way, because of where they have been,” said Humphries, using a blue rubber glove to examine an 1807 quarter-dollar that had been “well-circulated.”

Humphries said coins are tools for historians to piece together clues from ancient times on. Studying the ones chosen by Baltimoreans living in the throes of a fight by the fledgling nation to remain independent while building a bustling port city will help foster a deeper understanding of their lives.

“Why did they decide to include a medal of someone who is British? Why were they admiring Wellington in this monument to George Washington?” he said. “We haven’t figure that out yet. What do these specific choices mean?”

Paul Rubenson, the historical society’s exhibit manager, said watching the display spark Garrett’s interest and, in turn, produce an academic study brings history to life.

“This is the ultimate outcome: We always hope when people come in the door that what we put out will spur further interest and branch off in different directions,” he said. “This is just exponential.”

ywenger@baltsun.com

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