Question: I have never quite understood why the mintmark for New Orleans is “O” instead of “NO” since the mintmark for Carson City (also a city with a two-word name) is “CC” and not “C.” Do you know of any official reason for this or do you have any idea why this is so? –T. N.
Answer: The best that we can offer is a guess. In 1870 when the Carson City Mint began striking coins it had been less than a decade since the Charlotte Mint struck its final coins. Because of that, perhaps it was thought that using a single “C” as a mintmark might be confusing, especially as Carson City was to strike gold coins. So perhaps “CC” was chosen for clarity.
When the New Orleans Mint was opened in 1838, the single “O” was probably considered sufficient as there was no other United States mint (either in operation or in planning stages) that would use the letter “O” and cause confusion.
However, counter to the logic regarding Charlotte and Carson City, in 1906 when the Denver Mint opened, a single “D” was used to denote that facility, despite the fact that the “D” mintmark had been used from 1838 until 1861 on gold coins struck at the Dahlonega Mint. Perhaps it was felt that enough time had elapsed that no confusion would ensue.
As noted, this is just a guess. If you or any other readers discover further information, we would love to hear from you.