Depicts the seal of the United Mexican States.

The Seal of the United Mexican States is a modified version of the national coat of arms, with the addition of the full official name of the country Estados Unidos Mexicanos, in a semi-circular accommodation in the upper part of the seal. Current and past Mexican peso coinage have had the seal engraved on the obverse of all denominations.

The coat of arms depicts a Mexican golden eagle perched on a prickly pear cactus devouring a rattlesnake. To the people of Tenochtitlan this would have strong religious connotations, but to the Europeans, it would come to symbolize the triumph of good over evil (with the snake sometimes representative of the serpent in the Garden of Eden).

Upright ear of corn, numeral and date on left.

When looking for the different variants here are some of the most prominent details to look for:

• Sharp stem and wide date: 9 and 7 are noticeably apart, stem ends in a fine point, 10 in value is thinner, and corncob has 5 grain rows

• Blunt stem and narrow date: the whole date is packed together and the numbers are slightly thicker, stem is "bluntly" cut, 10 in value is thicker, and corncob has 6 grain rows

• Most of these details carry over to other dates and variant combinations; except for the grain rows that sometimes can be the same for both variants, or are the same for 2 out of 3 variants when a year has those many variants, but it is one of the easiest ways to identify them if the coin has some use and the stems are no longer pristine.