20 Francs Swiss National Bank

Switzerland's commemorative franc series has been issued annually since 1936, with each piece tied to a specific cultural or historical theme determined by the federal authorities. The 2007 issue falls within a long-running program that has accumulated enough die varieties and year-specific references to sustain its own dedicated collector literature — HMZ cataloguing for this series runs to multiple sub-entries per year.

The .835 fineness is the standard Swiss silver alloy used continuously for circulation and commemorative coinage since the Latin Monetary Union standardized it in 1865.