These pretty gold coins are worth their weight in gold, at a minimum, and more if you have one in fully uncirculated condition.
Here are the stats for the 5 and 10 pesos coins.
5 (CINCO) PESOS: 0.236 troy ounces gold content
10 (DIEZ) PESOS: 0.471 troy ounces gold content
To figure the base value of your coin, go to kitco.com and look up the current value of gold. Right now it is $1620 US dollars per troy ounce, but tomorrow it will be different. Be sure to look it up. Now multiply the price of gold by 0.236 for a 5 pesos or 0.471 for a 10 pesos coin to get the basic gold value. A 10 pesos, for instance, is worth today 0.471 x 1620 = $763, not too shabby.
When one of these coins is in extra-special numismatic (coin collector) condition, you can add a small premium to the basic gold value.
UNCIRCULATED 5 PESOS: add $50
UNCIRCULATED 10 PESOS: add $100
This gives an approximate retail value for your coin. If you are selling a coin to a dealer, he or she will offer you substantially less than retail. The mark-up keeps the dealership afloat.