Like the Krugerrand, the Mexican Libertad is a perfect coin. "The Libertad, unlike most gold and silver coinage in the world, does not show a face value; it shows only a weight. It can therefore change in value daily, assuming that the Mexican government were to also create a standard by which the Libertad prices could be calculated each day as the prices of gold and silver fluctuate." This quote taken from Jeff Thomas in his article: "The Mexican Libertad: The Currency Solution?"