Mexico: Peso 1918-1945 Cap & Rays


Quick Coinage Facts

Years Minted: 1918-1945
Composition: 80% Silver (1918-19), 72% Silver (1920-45)
Diameter: 34 mm
Weight: 18.13 grams (.4663 oz of silver 1918-19), 16.6 grams (.3856 oz of silver 1920-45)
Total Series Mintage: 467,825,000
Obverse Design: National Arms
Reverse Design: Cap & Rays
Edge: Lettered


Collectors of not just Mexican coinage but also of symbolic designs of liberty have made this one of North America’s most collected coins.

All coins were minted at the Mexico City Mint using large silver planchets (34mm) with a consistent high quality strike that gives all of the issues a beautiful presentation.

Additional reasons for the series popularity are due to the mintage figures. The Cap & Rays Peso is a fairly modern coin resulting in significant mintage totals that allowed for many examples to circulate among collectors throughout all of North & South America.

Given the silver content, size, design, and availability it is easy to understand the popularity of the series.


The obverse design features the Mexican coat of arms, An eagle clutching a snake while it perches on a prickly pear cactus. On the outer periphery is the phrase “ESTADOS UNIDOS MEXICANOS” or as translated to english “United Mexican States”.

The reverse design features a Phrygian Cap with Rays which has long been symbolic of liberty on American coinage. Below the design is a ¾ wreath with denomination “UN PESO” and date of issue above. In between the denomination and rays is the mint mark for the Mexico City Mint “Mo”.

The coin edge has incused lettering with the phrase "INDEPENDENCIA Y LIBERTAD" which is translated to "Independence and Liberty".

Obverse Reverse
Coin Edge

Major Varieties

To keep the peso value in line with silver prices the amount of silver was reduced from .4663 ounces to .3856 ounces in 1920.

Variety 1 – 1918-1919
Variety 2 – Reduced Silver 1920-1945

General Market Notes

Excluding proofs and errors, the keys to the series are the 1918 & 1919 issues in grades of XF or higher. The semi-keys are the 1920 & 1921 issues in grades above XF. Affordable examples of the key and semi-keys are available in grades of VF.

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