Mexico has one of the longest and most varied silver coining traditions in the world — stretching from the colonial 8 Reales of the 1500s through the iconic Cap and Ray pesos of the early 20th century. Mexican silver coins appear frequently in estate collections across North America, yet they’re often under-appreciated by collectors who aren’t familiar with the series. This guide covers the major silver coin types, their silver content, and current melt values so you know exactly what you’re holding.
For live, automatically updated melt values across all Mexican silver denominations, visit our Mexican silver coin melt value calculator.
A Brief History of Mexican Silver Coinage
The Casa de Moneda de México, established in 1535, is the oldest mint in the Americas. For three centuries under Spanish rule, Mexican silver — mined primarily in Zacatecas, Guanajuato, and San Luis Potosí — was struck into 8 Reales coins that circulated from Manila to Madrid. The iconic Pillar Dollar (Columnario type) and subsequent portrait coinage of the late colonial period are among the most historically significant coins ever produced.
After Mexican independence in 1821, the republic continued striking 8 Reales on the old colonial standard, now with republican imagery — the eagle and snake of the Mexican coat of arms replacing the royal bust. An 1863 decimal reform converted the system to a peso of 100 centavos, and the classic Cap and Ray peso design (featuring the Phrygian cap atop radiating sunbeams) became the signature motif of Mexican silver through the early 1900s.
A 1905 monetary reform reduced silver content across denominations, and silver gradually disappeared from Mexican circulation coinage by the mid-20th century — though Mexico continued striking iconic silver coins for collectors and investors, including the famous Onza and Libertad series.
Mexican Silver Coin Denominations and Specifications
8 Reales — Colonial and Early Republic (1537–1897)
The 8 Reales — the original “Piece of Eight” — is the foundation of Mexican silver collecting. Both colonial types (Pillar Dollar and Portrait series) and the republican eagle issues follow essentially the same standard: approximately 27.07 grams at .903 fine silver, giving an actual silver weight (ASW) of 0.786 troy ounces. This standard held remarkably consistent from the late colonial era through the end of the 8 Reales type in 1897.
Republican-era 8 Reales coins carry assay office initials identifying the mint — “Mo” for Mexico City, “Go” for Guanajuato, “Zs” for Zacatecas, “Pi” for San Luis Potosí, and others. Each assay office produced distinctive varieties that specialist collectors pursue by date and assayer combination.
Current melt value (8 Reales, .903 fine standard): 55
1 Peso — Cap and Ray Type (1866–1909)
Following the 1863 decimal reform, Mexico struck the 1 Peso as the direct successor to the 8 Reales, maintaining nearly identical silver content. The classic Cap and Ray peso weighs 27.073 grams at .902–.903 fine, for an ASW of approximately 0.7859 troy ounces. The obverse shows the Mexican eagle; the reverse features the Phrygian liberty cap surrounded by sunrays — the “Cap and Ray” motif that gives the series its collector nickname.
These coins were struck at multiple mints across Mexico, with the Mexico City “Mo” issues being most common. Date and mint combinations vary considerably in scarcity, and some are significant numismatic rarities. For the purposes of melt valuation, all standard Cap and Ray pesos share essentially the same ASW.
Current melt value (Cap and Ray Peso): 54.99
1 Peso — Caballito Type (1910)
The 1910 Caballito (“Little Horse”) peso is one of the most beautiful Mexican coins ever struck. Designed by French engraver Charles Pillet, its obverse shows a woman on horseback in full gallop — a dramatic departure from the static Cap and Ray design. Struck only in 1910 at 27.073 grams, .902 fine (ASW 0.7859 oz), the Caballito commands significant premiums over melt in all grades and is a cornerstone of any serious Mexican coin collection.
Current melt value (Caballito Peso, 1910): 54.99
1 Peso — Post-Reform Types (1918–1945)
A 1905 monetary reform reduced silver content across Mexican coinage, with the full impact felt by the later peso issues. The 1918–1919 peso was struck at 11.5 grams, .800 fine (ASW 0.2959 oz). The more common Aztec calendar peso of 1920–1945 — featuring the famous Aztec Sun Stone on the reverse — weighs 16.666 grams at .720 fine, giving an ASW of 0.3856 troy ounces. Despite lower silver content, the Aztec calendar peso is one of the most striking designs in world numismatics and is widely collected in its own right.
Current melt value (Aztec Calendar Peso, 1920–1945): 26.98
50 Centavos (1870–1945)
The 50 centavos closely mirrors the peso series in design and proportional silver content. The pre-reform type (1870–1905) weighs 13.536 grams at .902 fine for an ASW of 0.3925 troy ounces. Post-reform issues vary: the 1919–1945 type was struck at 8.333 grams, .720 fine, for an ASW of 0.1929 troy ounces. Always verify the date range when calculating melt value for a 50 centavos.
Current melt value (50 Centavos, pre-reform .902 fine): 27.46
Current melt value (50 Centavos, post-reform .720 fine, 1919–1945): 13.5
25 Centavos (1870–1892)
The 25 centavos was struck in .902 fine silver at 6.768 grams, giving an ASW of 0.1964 troy ounces. The series ended in 1892 and was not continued in the decimal peso era, making circulated examples relatively scarce compared to the larger denominations.
Current melt value (25 Centavos): 13.74
Complete Melt Value Reference Table
All values update automatically with the live silver spot price.
| Denomination / Type | Years | Weight | Fineness | ASW (troy oz) | Current Melt Value |
|---|---|---|---|---|---|
| 8 Reales (colonial & republic) | 1537–1897 | 27.07g | .903 | 0.7860 | 55 |
| 1 Peso – Cap and Ray | 1866–1909 | 27.07g | .902 | 0.7859 | 54.99 |
| 1 Peso – Caballito | 1910 | 27.07g | .902 | 0.7859 | 54.99 |
| 1 Peso – Aztec Calendar | 1920–1945 | 16.67g | .720 | 0.3856 | 26.98 |
| 50 Centavos (pre-reform) | 1870–1905 | 13.54g | .902 | 0.3925 | 27.46 |
| 50 Centavos (post-reform) | 1919–1945 | 8.33g | .720 | 0.1929 | 13.5 |
| 25 Centavos | 1870–1892 | 6.77g | .902 | 0.1964 | 13.74 |
For a complete denomination listing with live prices, use our Mexican silver coin melt value calculator.
Key Varieties and Collector Notes
The Assay Office System
One of the defining features of Mexican silver is the assay office (ceca) system. Because Mexico had multiple active mints throughout the republican era, each coin carries initials identifying both the mint and the individual assayer responsible for silver purity. The combination of mint mark, assayer initials, and date determines the true rarity of any given coin. Coins from the Mexico City mint (“Mo” or “M°”) are most common; coins from smaller regional mints like Alamos (“As”), Culiacán (“Cn”), or Hermosillo (“Ho”) are considerably scarcer.
Identifying Silver Mexican Coins
Not all Mexican pesos contain silver. Post-1945 Mexican pesos — while still carrying the peso denomination — were struck in stainless steel, cupronickel, and other base metals. The silver content cutoff for most denominations falls between 1945 and 1950 depending on the type. A simple rule: Mexican coins dated before 1945 carrying denominations of 8 Reales, 1 Peso, 50 Centavos, or 25 Centavos are almost always silver. For coins from the 1945–1960 transition era, verify the specific type against a reference before assuming silver content.
Mexico also struck a number of later 20th-century silver collector coins — the 1947–1948 Cuauhtémoc peso (0.1286 oz ASW), the 1950 Aztec Calendar peso (0.4178 oz ASW), and the silver Onza and Libertad bullion coins from 1979 onward. These are a separate collecting category from the historical circulation coinage covered above.
Collecting Mexican Silver: Practical Guidance
Cap and Ray pesos are the entry point. Common-date Mexico City issues in VF condition are readily available and represent excellent numismatic silver value — nearly 0.786 troy ounces of silver in a historically significant, beautifully designed coin. At today’s silver price, even a heavily worn Cap and Ray peso carries a melt value of 55.
The Caballito is a different market. The 1910 Caballito peso is universally recognized as a premium collector coin and always sells well above melt regardless of grade. If you encounter one at melt price, it’s worth acquiring.
Watch the post-reform date ranges carefully. The silver content reduction of 1905–1920 means that seemingly similar coins can have dramatically different ASW depending on the date. A pre-1906 peso has nearly twice the silver of a 1930s Aztec calendar peso. Always confirm the date range before applying a melt value calculation.
Multiple assay offices = multiple prices. If you’re buying Mexican silver for melt, common mint mark combinations are interchangeable. If you’re buying for numismatic value, regional mint issues from smaller assay offices can be significantly rarer and more valuable than their Mexico City counterparts with the same date.
Check Live Mexican Coin Melt Values
Silver prices move throughout every trading day, so melt values change constantly. Our Mexican silver coin melt value calculator updates in real time and covers the full range of Mexican silver denominations — from colonial 8 Reales through 20th-century issues. Use it any time you need a current melt value for a Mexican coin.
