U.S. National Archives (Record Group 104 [Denver], Entry 9, Records of Gold Bars Purchased, 1878 - 1883)
Records of Gold Bars Purchased, 1878 - 1883
National Archives online catalog entry is https://catalog.archives.gov/id/2641941. See also the National Archives & Records Administration numismatic finding aids at https://nnp.wustl.edu/library/archivedetail/538870.
Scanned at the National Archives in Denver, courtesy of John Graffeo.