What a centenario gold coin and the rest of the Mexican peso series are worth — how the 50 Peso’s 1.2057 troy oz of gold sets value, why most pieces are restrikes, and how to figure melt.
What Are Mexican Gold Coins?
Mexican gold coins are one of the most recognizable families of bullion in the world, and they all belong to a single denomination system: the peso gold series. The series runs from the small 2 Pesos up through the 2.5, 5, 10, and 20 Pesos, and culminates in the 50 Peso — the famous coin collectors and dealers call the Centenario. Every piece in this lineup was struck by the Mexican Mint, the Casa de Moneda de México, which was founded in 1535 and is the oldest mint in the Americas.
The single most important fact about the entire peso series is its consistency. Every denomination, from the dos pesos gold coin to the 50 Peso, is struck in the same alloy: 90% gold and 10% copper, which works out to .900 fine, or 21.6 karat. The copper is added for durability and gives the coins a warm, slightly reddish gold tone. Because the fineness never changes across the series, the gold content scales directly with the peso number — a 20 Peso holds exactly ten times the gold of a 2 Peso.
That predictable structure is exactly why Mexican gold coins are so popular with both investors and families who inherit them. Once you know the denomination, you know the gold content, and once you know the gold content you can estimate value against the live gold price. We see the Centenario, the dos pesos, and the 2.5 peso gold coin come across our counter constantly here in San Antonio, and the first thing we explain is how this clean .900 fineness makes the math straightforward.
The 50 Peso Centenario: 1.2057 Troy Ounces of Gold
The 50 Peso Centenario is the flagship of the series and the reason most people search for a centenario gold coin in the first place. It was first struck in 1921 to mark the 100th anniversary — the centennial — of Mexican independence, which is how it earned the name Centenario. The coin’s obverse features the Winged Victory, the Angel of Independence (El Ángel) that stands atop the famous monument in Mexico City, with the volcanoes Popocatépetl and Iztaccíhuatl rising behind her. The reverse carries the Mexican coat of arms: a golden eagle perched on a cactus, devouring a serpent.
What makes the gold centenario stand out is its sheer size. A single 50 Peso contains 37.5 grams of pure gold, which equals 1.2057 troy ounces — one of the largest gold contents of any regularly traded bullion coin in the world. The full coin weighs about 41.66667 grams total because of the 10% copper alloy, but the gold weight that drives its value is that 1.2057 troy ounces. For a buyer who wants a large, single-coin gold position rather than a stack of smaller pieces, the Centenario is hard to beat.
It is important to understand that the vast majority of Centenarios in the market today are official restrikes. After the original early issues, the Mexican Mint produced restrikes — reacuñaciones — for bullion purposes, and the 50 Peso is most commonly dated 1947 and dual-dated 1821-1947. These restrikes are not rare dates; they were made specifically to trade as gold bullion. That is the single biggest point of confusion we clear up: a 1947-dated Centenario is genuine Mexican Mint gold, but it trades on its gold content, not as a scarce collectible.
The Smaller Pesos: Dos Pesos, 2.5, 5, 10 & 20
Below the Centenario sits a full range of smaller denominations, each holding its proportional share of gold. The 2 Pesos, often called the dos pesos gold coin, contains 1.5 grams of pure gold (0.0482 troy oz) in a coin weighing 1.66667 grams total. The 2.5 peso gold coin holds 1.875 grams of pure gold (0.0603 troy oz), the 5 Pesos holds 3.75 grams (0.1206 troy oz), and the 10 Pesos holds 7.5 grams (0.2411 troy oz). The dos pesos and 2.5 peso are most commonly dated 1945 and, like the Centenario, are usually official restrikes rather than rare originals.
The 20 Pesos is a favorite among collectors for its design. It holds 15 grams of pure gold (0.4823 troy oz) and its reverse displays the Aztec Sun Stone — the Piedra del Sol, popularly known as the “Aztec calendar.” That instantly recognizable carved disc makes the 20 Peso one of the most visually distinctive coins in the series. The 2.5, 5, and 10 Peso obverses feature Miguel Hidalgo, the father of Mexican independence, while the small 2 Peso simply shows the value and date.
Because every denomination shares the same .900 fineness, the smaller pesos are essentially fractional versions of the same gold standard. They let buyers own Mexican gold in more divisible amounts, much like fractional bullion coins from other mints. The tradeoff, as with any smaller gold coin, is that the cost per troy ounce of gold tends to be a bit higher on the small pieces than on a large coin like the Centenario, simply because minting effort does not shrink as fast as the coin does.
How Mexican Gold Coin Value Is Calculated
The baseline value of any Mexican gold coin is its melt value: the amount of pure gold it contains multiplied by the current gold spot price. Because the entire peso series is .900 fine, the pure gold weight is fixed and published for each denomination, so the calculation is conceptual and clean. For a Centenario, you take its 1.2057 troy ounces of pure gold and multiply by the gold spot price. For a dos pesos, you use its 0.0482 troy ounces. The denomination tells you the gold weight, and the gold weight times spot gives you the melt baseline.
This is why the peso series is so easy to value relative to coins with odd or mixed purities. A 20 Peso’s 0.4823 troy ounces, a 10 Peso’s 0.2411 troy ounces, and a 5 Peso’s 0.1206 troy ounces all follow the same simple formula. We always point buyers and sellers to our live gold price page so they can see the current market for themselves, then apply the pure gold weight for whichever coin they hold to estimate where melt sits at that moment.
For most Centenarios, dos pesos, and other restrike pieces, melt is very close to the whole story, because these coins trade as bullion. The premium over melt — the small amount above gold content that reflects minting, recognition, and dealer costs — moves with market conditions and tends to be modest on common restrikes. Scarce original dates and high-grade certified examples are the exception, and we cover those next.
Restrikes vs. Original Dates: What Affects Value
The biggest factor separating a melt-value coin from a premium coin is whether it is a common restrike or a scarce original issue. As noted, official restrikes — the 1947 Centenario and the 1945 dos pesos and 2.5 peso, among others — were produced in large numbers specifically to trade as bullion. They are genuine Mexican Mint gold, fully recognized, but they are not rare, so they trade at or near their gold content. The overwhelming majority of Mexican gold coins changing hands today fall into this category.
Original early-date issues are a different matter. Coins struck in their original years, and certain scarce dates within the series, can carry numismatic premiums above melt because of their lower surviving populations and collector demand. For these pieces, condition and eye appeal matter, and a coin certified by PCGS or NGC at a high grade can be worth meaningfully more than a worn example of the same date. The Aztec calendar 20 Peso and well-preserved early Centenarios are examples where collectors will look beyond gold content.
For the typical buyer or seller, the practical takeaway is simple: identify whether your coin is a common restrike or a potentially scarce original before assuming a value. A 1947 Centenario or a 1945 dos pesos is bullion; an unusual early date might be more. When in doubt, an in-person look from a dealer who handles these coins regularly is the fastest way to know which category you are in, and whether certification is worth pursuing.
Buying and Selling Mexican Gold Coins
Lone Star Coins buys and sells the Mexican Gold Centenario (50 Peso), the dos pesos, the 2.5 peso, and the full peso gold series at live gold spot-based pricing. As a family-owned PCGS/NGC Authorized Dealer with more than 40 years in San Antonio, we handle everything from a single inherited Centenario to a full set of the peso series, and we explain exactly how the gold content and any collector premium factor into the number.
If you inherited Mexican gold coins and are not sure whether you are holding common restrikes or something scarcer, we offer free walk-in evaluations at our San Antonio showroom, with same-day payment when you sell. We can show you the spot-based math right at the counter — pure gold weight times the live gold price — so you can see precisely how we arrive at a Centenario or dos pesos figure, and whether any of your coins carry a premium over melt.
Whether you are adding a large single-coin gold position with a Centenario, comparing the peso series to other bullion, or selling coins that have been in the family for years, you are welcome to stop by in person or reach us about nationwide shipping. We are glad to answer questions first and let you decide what fits your goals — no pressure, just straight information.
Frequently asked questions
How much is a Mexican 50 Peso gold coin (Centenario) worth?+
A Centenario is worth at least its melt value: 1.2057 troy ounces of pure gold multiplied by the current gold spot price. Most Centenarios are official restrikes that trade as bullion close to that gold content, with a modest premium. Scarce original dates can be worth more. Check our live gold price page for the current market.
How much gold is in a Centenario?+
A 50 Peso Centenario contains 37.5 grams of pure gold, which equals 1.2057 troy ounces — one of the largest gold contents of any regularly traded bullion coin. The full coin weighs about 41.66667 grams because of the 10% copper alloy, but it is that 1.2057 troy ounces of gold that drives its value.
What is a dos pesos gold coin worth?+
A 2 Pesos (dos pesos) gold coin contains 1.5 grams of pure gold, or 0.0482 troy ounces. Its melt value is that gold weight times the current gold spot price. Most dos pesos are 1945-dated official restrikes that trade as bullion near melt rather than as rare collectibles. See our live gold price page for today’s market.
Are Centenarios and dos pesos restrikes, and does that affect value?+
Yes — the majority in the market are official restrikes (the 50 Peso commonly dated 1947 and dual-dated 1821-1947, the 2 and 2.5 Peso commonly dated 1945). They are genuine Mexican Mint gold but were made for bullion, so they trade on gold content, not as rare dates. Scarce original issues can carry premiums over melt.
How is the value of a Mexican gold coin calculated?+
Take the coin’s pure gold weight and multiply it by the live gold spot price. Because the whole peso series is .900 fine, each denomination has a fixed gold weight — for example, 1.2057 troy oz for the 50 Peso, 0.4823 for the 20 Peso, and 0.0482 for the 2 Peso. That melt figure is the baseline; common restrikes trade close to it.
What is the difference between the Centenario and a 1 oz gold coin?+
A 1 oz coin holds one troy ounce of pure gold, while a Centenario holds 1.2057 troy ounces — so a single Centenario carries more gold than a standard one-ounce coin. Both are .900-or-higher bullion that tracks the gold price; the Centenario simply packs a larger, single-coin gold position into one piece.
Where can I sell Mexican gold coins in San Antonio?+
Lone Star Coins buys the Centenario, dos pesos, 2.5 peso, and the full Mexican peso gold series at live gold spot-based pricing, with free walk-in evaluations and same-day payment. We are a family-owned PCGS/NGC Authorized Dealer with 40+ years in San Antonio, and we also offer nationwide shipping.