1/20 oz Silver Libertad 1991: Value & How to Sell

If you inherited or found a tiny 1991 Mexican silver coin marked "1/20 Onza," here is the honest answer: most examples are worth a few dollars, driven mainly by their small silver content. A certified high grade can push the price higher, but this is not a life-changing coin. Here is what it actually is and what it sells for in 2026.

What you actually have

The 1/20 Onza Libertad ("Libertad" means Liberty) is a fractional silver bullion coin from Mexico. The 1991 issue was part of the first year Banco de México, the country's central bank, added fractional sizes to its silver Libertad line, letting collectors own the famous Winged Victory design in a small format.

Key specs, exactly as struck:

• Metal: .999 fine silver (99.9% pure)
• Weight: 1.55 grams (that is 1/20 of a troy ounce)
• Diameter: 16.01 mm
• Edge: reeded
• Mint: Casa de Moneda de México (the Mexican Mint)

The front (obverse) shows the Mexican national coat of arms, an eagle on a cactus. The back (reverse) shows the Winged Victory statue from Mexico City's Angel of Independence monument, with the volcanoes Popocatépetl and Iztaccíhuatl behind her. This is one of the most admired designs in modern coinage.

The 1991 coin uses the original 1982 to 1995 die, nicknamed the "cuño gordita" (roughly, "chubby die") by Mexican collectors. It is slightly smaller in diameter and thicker than the modern die used since 1996. That distinction matters to specialists but not much to the casual seller.

What it's worth

Because it is a bullion coin, this piece has a price floor: its melt value. At 1.55 grams of pure silver, that floor is small, roughly the value of about 0.05 troy ounces of silver. In practical terms, a worn or circulated example trades close to melt, often just a few dollars.

The premium comes from two things: it is a small denomination that fewer people saved, and demand from collectors completing a Libertad set. A clean uncirculated coin sells for more than melt, and a certified Mint State example in a graded holder (NGC or PCGS) can bring a meaningful multiple over spot. This is not a rare-key-date situation. Do not expect thousands of dollars for a raw circulated piece.

Coin	Year	Condition	Approx. value (USD)
1/20 oz Silver Libertad	1991	Circulated / worn	Near melt, a few dollars
1/20 oz Silver Libertad	1991	Uncirculated (raw)	Small premium over melt
1/20 oz Silver Libertad	1991	Certified MS-65+ (NGC/PCGS)	Multiples of melt, condition-driven

Banco de México does not publish official mintage figures for this era, since public production records begin in the year 2000. That means no confirmed mintage exists for the 1991 fractional. Some collector forums speculate on numbers, but none are verified, so treat any exact "only X made" claim with skepticism.

The myth to ignore

A small, old-looking silver coin from Mexico gets people imagining a fortune. For this piece, that is not the reality. Value here is tied to silver content plus a modest collector premium, not to legendary rarity. The coins that break records at auction are 19th-century rarities and gold pieces, not a 1991 fractional bullion coin. Read our guide to the most valuable Mexican coins if you want to see what actually commands high prices.

How to check if yours is genuine

Start with the specs. A real 1991 1/20 oz Libertad weighs 1.55 grams and measures 16.01 mm. If your coin misses those numbers, be suspicious. You can also do a simple ping test: genuine silver rings with a high, sustained tone when balanced on a fingertip and lightly tapped, while fakes sound dull and short. For anything you believe is worth real money, professional grading by NGC or PCGS is the definitive check, it confirms authenticity and grade in one sealed holder.

Where to sell it

Your best options in the US are:

• Local coin shops (LCS) that buy silver bullion and world coins. They can assess it on the spot.
• Online dealers and marketplaces that specialize in silver, where fractional Libertads have a steady buyer base.
• Certified auction only if you have a top-grade example worth the grading fee.

Because this is a precious-metal coin, only deal with buyers who let you verify weight and see the coin (or clear photos of the obverse, reverse, and edge) before money changes hands. For collector-to-collector deals and second opinions, the Pesoteca buy-and-sell forum connects you with people who know the Libertad series. To sell fast, photograph both sides and the edge, confirm the specs above, and compare against current silver spot before accepting an offer.

Want to know what your fractional Libertad set is worth as a group, or whether you have the harder-to-find sizes? Post your coins in the Pesoteca forum and let the community weigh in.

1/20 troy ounce Libertad silver 1991 Regular BU

This piece is the 1/20-troy-ounce silver Onza Libertad, struck by the Mexican Mint in 1991 in its Regular BU version.

Technical data. It contains 1.55 g of pure silver, .999 fineness, and measures 16 mm in diameter. The reverse bears the effigy of the Angel of Independence, chosen by Banxico as the official symbol of the series since 1981. The obverse shows the National Coat of Arms in its pre-1969 version, alongside other historical coats of arms as the family's identity mark.

Role within the set. It is the smallest fraction of the set. It serves as an initiation piece, a gift, or a first contact with the series: it costs little per example but carries the highest premium in the family over the value of the silver it contains, because the die cost is spread over fewer grams.

Context of the year. In 1991 Carlos Salinas de Gortari was in office. The set's fractions were expanded: 1/20, 1/10, 1/4, and 1/2 ounce were added to the full ounce. It is the starting year of the fractional set in silver.

Regular BU finish. The Regular finish, cataloged by Banxico as satin or BU, is obtained with dies without special polishing. The result is an even matte shine across the whole surface, with no mirror contrast between fields and reliefs. It is the traditional bullion finish: bought for its weight in pure silver plus a modest die premium. It is the version hunters look for to build the complete set by year without decapitalizing themselves on every piece.

Mintage. The exact mintage of this combination does not appear in the Bank of Mexico's public 2000-2025 tables. For pieces outside that range, the specific Mint catalog must be consulted.