Rarity depends on the mintage and the number of specimens still in circulation.
19121 franc - Albert I in Dutch
19121 franc 1912 Albert I - Albert King of the Belgians
191250 centimes - Albert I in Dutch
191250 centimes - Albert I in French
1912Mexico 10 centavos 1912 M
1912Netherlands ½ gulden - Queen Wilhelmina - 1912
19132 Korona - Francis Joseph I
1913France 10 centimes 1913 - Daniel-Dupuis
1913Germany 3 marks - Wilhelm II 1913
1913Netherlands 25 Cents - Queen Wilhelmina - 1913
1914Guernsey 2 doubles 1914 - Coat of Arms
1914Mexico 50 centavos 1914 M
1914Netherlands 10 Cents - Wilhelmina - 1914
1915Italy - 1915 1-lire R - Victor Emmanuel III
1917Canada 5 cents - George V 1917
1917Germany 10 pfennigs 1917
1919Norway 1 øre 1919
1921Mexico 2 pesos 1921 Mo - Centenary of Independence
1921Portugal 10 centavos 1921
1921Portugal 20 centavos 1921
1924Germany 1 REICHSPFENNIG 1924 G
1924Norway 25 øre 1924
1924Portugal 1 escudo 1924
1925Germany 1 reichspfennig 1925-F