100 Pesos 1 Kilogram Silver Coin (2008): What It's Worth

If you inherited or found a massive Mexican 100 pesos coin the size of a small saucer, you are holding a full kilogram of pure silver. This is not spare change. As of 2026, its floor value tracks the silver market, and one kilo of .999 silver is worth roughly 800 to 1,000 USD at recent spot prices, before any collector premium.

What you actually have

This is the 100 Pesos 1 Kilogramo de Plata, struck by Mexico's central bank (Banco de México) in 2008. "Kilogramo" is Spanish for kilogram, and that is the point: the coin contains a full 1,000 grams of silver. It is a bullion and commemorative piece, not a coin that ever circulated in anyone's pocket.

Here are the exact specs, which matter for both value and authentication:

Spec	Detail
Face value	100 pesos
Year struck	2008 (single year of issue)
Weight	1,000 grams (1 kilogram)
Diameter	110 mm
Metal	Silver, .999 fine (99.9% pure)
Edge	Plain (smooth)
Era	Modern Nuevos Pesos and current era

The 110 mm diameter is enormous, more than four inches across. If your coin is noticeably smaller or lighter than 1,000 grams, it is not this issue.

What it's worth in USD

The honest answer has two layers.

Melt value (the floor). With one kilogram of .999 silver, this coin can never be worth less than the silver in it. That gives it a hard floor tied to the international silver spot price. At recent prices, that floor sits in the 800 to 1,000 USD range. When silver rises, the floor rises with it. This is why big silver coins like this one are considered safe to own: there is always a buyer at melt.

Collector premium (the upside). Above melt, condition and demand decide the number. A coin still sealed in its original Banco de México case with certificate will bring more than a loose, handled example with fingerprints and hairline scratches. Certified pieces graded by NGC or PCGS command the strongest premiums. For a clean, well-preserved example, expect a modest premium over melt rather than a dramatic multiple, since this is primarily a silver-content coin, not an ultra-rare rarity.

We will be straight with you: this is not a coin that turns up in headlines about pieces selling for millions. Its value is real and substantial because of the silver, but do not expect a jackpot beyond metal plus a reasonable collector markup.

Mintage: why there's no headline rarity number

The exact mintage for this 2008 issue is not published in official Banco de México figures. That usually means it was released in limited numismatic sets or as a short, specific issue rather than a mass production run. Collector forums float various numbers, but none are confirmed, so treat any "only X ever made" claim with skepticism. The single-year 2008 date means there are no year variants to chase within this issue.

How to tell if yours is genuine

With a coin holding this much silver, fakes exist. Three quick checks:

1. Weigh and measure it. It must weigh 1,000 grams and measure 110 mm across. A digital kitchen scale settles this fast. Counterfeits almost always miss on weight because real silver is dense and expensive to replicate.
2. The ping test. Balance the coin on a fingertip and tap it lightly. Genuine .999 silver produces a high, clear, sustained ring. Fakes and plated base metal sound dull and short.
3. Get it certified. For a piece worth several hundred dollars or more, professional grading by NGC or PCGS is the definitive proof. A slab certifies both authenticity and grade, and it raises resale value.

Check the coin grading guide to judge condition before you sell, since grade is the single biggest factor above melt.

Where to sell it

Because this is a precious-metal coin, you want a buyer who will verify weight and metal in front of you and pay close to a fair spot-plus-premium price.

• A verified numismatic dealer from the Pesoteca directory will appraise and weigh it on the spot, which is the safest route for a high-value silver piece.
• The Pesoteca buy-and-sell forum connects you directly with collectors, often at better prices than a dealer's buy rate.
• Reputable bullion dealers will always pay at least melt, which sets your walk-away floor.

Before selling, photograph the obverse, reverse, and edge, and confirm the coin's grade. Do not dump it on the first social-media offer. Because of the metal value, only deal with buyers who let you verify weight before money changes hands.

Have one sitting in a drawer and want a read on grade or authenticity? Post clear photos of both faces and the edge in the Pesoteca forum and let collectors weigh in before you sell.