Previous years for the 50 francs were made of CuNi (KM#6), and 100 francs was made of Nickel (KM#4).
The 2012 & 2013 items are reported to be new material, iron with galvanized nickel, so they are new types.
For the new 50 francs, it's weight is 4.82 grams instead of the previous 5.00. Besides, the 100 francs weights 6.70 grams, while the nickel type was 7.00. The other small golden denominations haven't changed.
(information and image from Michel Guerin and Wolfgang Schuster)