1/2 Oz Danbury Mint Decades of Progress 1870 Round PF

The Danbury Mint produced a series of 1/2 Oz rounds commemorating significant achievements within each decade. The series was called Decades of Progress. The mintage for the rounds is unknown. 

Obverse: The obverse design depicts Thomas Edison sitting at a table working on a lightbulb. The phrase "UNITED STATES OF AMERICA" is inscribed at the top, with the decade "1870s" found at the lower left. The description "EDISON'S LIGHT BULB" is inscribed at the bottom. 

Reverse: The reverse features the common design of the series. The central feature is a depiction of Bohr's model of the atom. Surrounding the atom are images representing important inventions such as a chemistry flask, the lightbulb, the gramophone, eyeglasses, a rocket, and the airplane. The motto "E PLURIBUS UNUM" is inscribed at the top while the weight, purity, and content of "1/2 TROY OUNCE .999 FINE SILVER" is located at the bottom. The mint mark of "D/M" is centered within it.