U.S. National Archives (Record Group 104, Entry 212, Letter Index for 1792 to 1835) Pubblico Deposited
Index of correspondence received and sent from the United States Mint and its Officers, 5/5/1792-7/16/1835.
The National Archives catalog record is at https://catalog.archives.gov/id/7064802. See also the National Archives & Records Administration numismatic finding aids at https://nnp.wustl.edu/library/archivedetail/538870.