Denver Mint records scanned at the National Archives (NARA) in Denver - covering the period 1947 - 1971. Record group 104.  Information resource name and date range: “Record Books of Heat, Water, Gas, and Fuel Costs, 1947 - 1971.”  Courtesy of John Graffeo.  

NARA description: This series consists of ledgers of heat, water, gas and fuel expenditures. This series contains accounting ledgers that detail the costs of the U.S. Mint, Denver's power and fuel consumption, and the costs involved.

NARA catalog entry: https://catalog.archives.gov/id/2674981.

Denver Mint records scanned at the National Archives (NARA) in Denver - covering the period 1909 - 1934. Record group 104.  Information resource name and date range: “Record of Deposit Received by Mail Express, Oct. 5 1909 - Apr. 24 1914.”  Courtesy of John Graffeo. 

NARA description: This series consists of records of deposits received by express mail. The records include the dates the mail was received, the amount of the deposit, and a brief description of the transaction.

The NARA catalog entry is https://catalog.archives.gov/id/2674936.

The National Archives catalog entry is https://catalog.archives.gov/id/2674940.