US Mints.

The US mint has a web site at www.usmint.gov

There were 8 US mint locations of which 4 are still active

C- Charlotte, North Carolina Gold coins only operating between 1838 and 1861

CC- Carson City, Nevada operating between 1870 and 1893

D-Dahlonega, Georgia Gold coins only operating between 1838 and 1861

D- Denver, Colorado started operating in 1906 still in operation today

O- New Orleans, Louisiana operating between 1838 and 1909

P- Philadelphia, Pennsylvania started operating in 1793 still in operation today

S- San Francisco, California started operating in 1854 still in operation today

W- West Point, New York started operating in 1984 still in operation today