The masonry team working to restore the structure said they found a box inside the Abigail Adams Cairn that was inside a brick-lined chamber at the landmark's center and covered with a slab of granite, the Quincy Patriot Ledger reported Wednesday.
The time capsule was taken to the historical society at the Adams Academy to determine the best way to open the soldered-shut metal box.
"Usually it's everyday materials; it's not like we're going to find the secret of the ages in there or anything like that," said Ed Fitzgerald, director of the Quincy Historical Society. "Purely things of historical interest, not anything of value. No one is going to put their diamonds in there."
However, Quincy Mayor Thomas Koch expressed excitement at the find.
"What started as sort of a mundane project has now got some excitement to it,'' he said. "I'm anxious to see what kind of items would be included. It's kind of fascinating."