Mexican 25 pesos 1968 Olympic KM#479 coin value

The image of this coin is simply an example of Mexico 25 pesos 1968 Olympic type coinage.
Cost approximate and valid for common coin only (without rare varieties).
I do not buy or sell coins - this is just a catalog.

Currency - Peso=100 centavos
Type - commemorative coin
Composition - Silver 0.720
Diameter - 38.0 mm
Weight - 22.50 grams
Edge: Inscription "INDEPENDENCIA Y LIBERTAD"Years of mintage:
1968
Reverse:
Olympic rings below left native dancing
Legend:
JUEGOS DE LA XIX OLIMPIADA MEXICO 1968
Obverse:
National emblem and garland
Legend:
25 PESOS / LEY 0.720 / ESTADOS UNIDOS MEXICANOS
Krause catalog number - KM#479
Coin value in "UNC" - 15-20 USD