The Twenty Centimes coin is a small circulating denomination of the Swiss Franc. Given that Switzerland has four official languages, the sub-unit of the Franc has four different names; it is centime (c.) in French, Rappen (Rp.) in German, centesimo (ct.) in Italian and rap (rp.) in Romansh. Some English-language catalogues call the coin a 20 Rappen coin, but the English-language publications of the Swiss National Bank and Swissmint prefer the term 20 centimes.
This first version of the 20 centimes / rappen coin was designed by Carl Friedrich Voigt of the Munich Mint (then Royal Bavarian Mint). On the obverse it featured the Swiss Coat of Arms (a rendering quite different from that on the One Centime and Two Centimes denominations released at the same time but designed by Alexander Hutter), on two flower (Alpine rose) branches. The reverse shows the value (only a numeral, no text) within a flower wreath. This original reverse has remained unchanged and is still used on current coins. This version was lighter (3.25 grams) and made of billon (an alloy with a very low quantity of silver), the composition of which varied through the years: 15% silver, 50% copper, 25% zinc, 10% nickel (1850, 1851), 15% silver, 75% copper, 5% zinc, 5% nickel (1858), 15% silver, 65% copper, 10% zinc, 10% nickel (1859).
In 1881, the obverse was changed to a design by Karl Schwenzer featuring the effigy of Libertas. The metal was changed to pure nickel and the coin became heavier (4 grams).
The first version was issued only until 1859 and was demonetised on 30th June 1886.
The reverse shows the value 20 (only a numeral, no text) within a wreath of flowers (Alpine roses). This original reverse has remained unchanged since 1850 to present.
The mint mark is under the ribbon tying the wreath: BB for the Strasbourg Mint in 1850 and 1851, B for the Bern Mint later.