Swiss Gold 20 Francs Vreneli Helvetia (Random Year) Year: Random Years Country: Switzerland Denomination: 20 Francs Metal Content: 0.1867 troy oz Purity: .900 Gold Thickness: 1.4 mm Diameter: 21 mm Minted starting in the late 19th century. These Gold coins are attractive to look at with a spectacular design. Minted at the Bern Mint from 1897-1935 and again in 1947 and 1949.