The last ones issued for circulation where 100 pesos coins, there is two types for each state of México (32 states=64 coins in total) the first type have the coat of arms of each state (issued from 2003 to 2005) and the second type has the image of a representative place of each state (issued in 2007) in his days and until today people (that dont now about numismatics) dont like them and toss them away or change them in the bank, but Banco de México is now melting them! so i am trying to save them, they are found in circulation yet
They were minted from 2003 to 2007
They have 1/2 ounce of sterling silver (.925)

Example of first and secong type for Jalisco
There are other silvers in circulation, but they are a little bit older, 10, 20 and 50 nuevos pesos minted from 1992 to 1995, they are way much rarer than the 100 pesos coins, because more people where aware of their silver content, but if its your lucky day you'll maybe find one in your change (10 nuevos pesos is the most likely to find, 20 nuevos pesos in banks, but 50 nuevos pesos its nearly impossible)

10 Nuevos pesos (.925 silver center)

20 Nuevos pesos (.925 silver center)

50 Nuevos pesos (1/2 ounce of .925 silver)
Mexico is maybe the last country to produce silver for circulation, just today Banco de México told in a conference that coinage desing will be changed in 2018, so this coins are going expensive in some years, it stills a mystery for me how México been the biggest silver producer since 1600's, has to sell and control his own silver as the enterprises and the economists say? mad world