10 Pesos 1979 (Hidalgo, Seven-Sided): What It's Worth

If you inherited a seven-sided Mexican 10 pesos dated 1979, here is the honest answer: in worn, circulated condition it is worth a few cents to a couple of dollars, and it usually sells only in bulk lots. Mexico struck about 57.2 million of them, so this is one of the most common coins of its era. Only uncirculated examples or genuine mint errors carry real money.

What this coin actually is

The 1979 10 pesos is a copper-nickel coin struck by the Casa de Moneda de México (the Mexican Mint). It carries the profile of Miguel Hidalgo y Costilla, a leader of Mexican independence and one of the most repeated faces on 20th-century Mexican coinage. The obverse shows the national coat of arms, the eagle devouring a serpent.

The standout feature is the shape: it is heptagonal, seven-sided, not round. That was a deliberate design choice so people could tell the denomination apart by touch. This design ran from 1974 to 1985 and is cataloged as KM# 477.

Key specs, exactly as struck:

• Metal: copper-nickel (roughly 75% copper, 25% nickel). No silver, no gold.
• Weight: 13.97 g (14 g nominal), the thick-flan version.
• Diameter: 30.5 mm.
• Edge: reeded.
• Mint mark: Mo (Mexico City).
• Mintage: about 57,200,000 for the 1979 date.

Is it worth money?

For almost everyone reading this, no, not in any meaningful way. Copper-nickel has no intrinsic bullion value worth calculating, so there is no metal floor like there is with silver coins. Everything comes down to condition.

• Circulated (worn): a few cents to about 2 USD, typically sold by the handful.
• Uncirculated (UNC), original mint luster, clean relief on Hidalgo: this is where the small premium lives. International listings for uncirculated coins from this series have sold in the range of roughly 5 to 61 USD depending on grade.
• Certified in high mint state (NGC/PCGS MS-65 and above): the top of that range, and only if the grade is genuinely there.

Because the mintage was enormous, this is a beginner's coin, the kind you use to start a Mexican type or date set, not a coin that funds a vacation.

The myth: "old Mexican coin, must be valuable"

This coin gets pulled out of drawers constantly, and people assume age plus foreign country equals fortune. It does not. A coin made in the tens of millions and still turning up in family collections 45+ years later is common by definition. Age alone drives nothing here. What drives value is rarity (how many survive in top grade), demand, and condition, and this coin fails the rarity test.

The one exception is errors. On a print run this size, genuine mint errors do exist: off-center strikes, doubled dies, wrong planchets. These are the only thing that lifts a 1979 10 pesos above lot value, and they are uncommon. Never assume you have one. Get any suspected error verified by a specialist before you attach a premium.

How to tell if yours is genuine

Counterfeits of a low-value coin like this are rare, but check the basics:

• It should be seven-sided, not round. A round example is a red flag.
• Weight near 13.97 g and diameter near 30.5 mm. Weight well below expected is a warning sign.
• Hidalgo's bust facing left, with the legend DIEZ PESOS, the year 1979, and the Mo mint mark.
• Copper-nickel gives a silvery look; it should not appear yellow or brassy.

Where to sell it

Because it is so common, this coin sells cheap and usually in bulk. Realistic options:

• Bulk lots on general marketplaces if you have many low-grade coins together.
• A coin dealer if you have a genuinely uncirculated example worth grading. To compare real prices before you sell, check the Pesoteca shop directory and cross-reference offers before closing any deal, especially if your coin is uncirculated.

If you have a whole box of inherited Mexican coins, sort out the silver pieces first, since those have a real metal floor, and treat the copper-nickel coins like this one as the common tier.

Have a 1979 10 pesos you think might be a mint error, or an uncirculated piece you want a second opinion on? Post clear photos of both sides in the Pesoteca forum and let the community weigh in before you sell.

Mexican circulating peso coins from the second half of the 20th century were struck in alloys that changed according to the cost of metals and inflationary processes: .720 silver in the $1, $5, $10, $25 denominations during the 1940s-50s; cupronickel from the 1970s on; aluminum bronze and stainless steel in the 1980s; pieces with figures (Hidalgo, Cuauhtémoc, Juárez, Madero) in the late 1980s just before the transition to Nuevos Pesos in 1992. 1979 corresponds to the period when this variant was in circulation.