1917, Kingdom of Serbia, Peter I. Nice Copper-Nickel 20 Para CoinMint Year: 1917 Reference: KM-20. Denomination: 20 ParaMaterial: Copper-NickelDiameter: 22mmWeight: 5.6gmKing Peter I is remembered for his modesty, attributed to his military background. He was immensely popular throughout his reign and remains one of the Western Balkans’s most popular leaders. He is considered to be ...