According to Martin Armstrong: https://www.armstrongeconomics.com/.../thomas-jefferson-the-ancient-coin-collector/
several coin dealers still haven't recouped losses from Armstrong's Ponzi scheme-- https://en.wikipedia.org/wiki/Martin_A._Armstrong
Maybe because it was a 1797 half dime? I have no idea where Armstrong came up with this "Jefferson coin" story or that it was a denarius. What I found was this: Scroll down to the 1797 paragraph. "In June, Jefferson received from the U.S. Mint dimes and half-dimes to the value of $300.00. A half-dime of 1797 was uncovered in archaeological excavations at Monticello." If a denarius had been found at Monticello, surely the official website would have mentioned it. https://www.monticello.org/research-education/thomas-jefferson-encyclopedia/coin-collection/ Also this 1981 NY Times article. "When Mr. Kelso's digging yielded a 1797 half dime - before the vintage of the contemporary Jefferson nickel, with its Monticello face - the household records here explained it. They show that Jefferson sent $600 to the United States Mint for a special coinage of the half dimes to pay the artisans at work on his house." https://www.nytimes.com/1981/11/19/garden/monticello-regains-18th-century-look.html There's supposedly research on Jefferson's collection on NNP as mentioned here https://nnp.wustl.edu/library/periodical/630398 but I'll be danged if I can find it. Maybe someone else is better at searching for it there.
https://archive.org/details/epnbox20-thomasjeffcollection/mode/1up might be the research mentioned above. I still don't see a list of Jefferson's ancient coins.
