1 Kilo Silver Aztec Calendar 100 Pesos (2013): Value & How to Sell

If you inherited or found a heavy silver disc with the Aztec Calendar (Sun Stone) on the back and "100 Pesos" on the front, you have something with real weight behind it, literally. This is Mexico's one-kilo silver bullion coin from 2013. Its value starts at whatever a kilo of silver is worth on the day you sell, and climbs from there depending on condition and demand.

What it's worth right now

This coin is a bullion piece, which means its baseline value tracks the silver market. It contains one full kilogram of silver (32.15 troy ounces), so its melt value alone runs into the hundreds of dollars and moves every day with the spot price. To get your floor, multiply the current price of silver per troy ounce by 32.15.

Because it is a large, low-mintage silver piece rather than a mass-circulated coin, it usually trades at a premium over melt among collectors. A clean example in original mint condition, ideally still in its Banco de México capsule with certificate, sells for more than a scratched or handled one. In 2026, expect a range from spot silver at the low end to a meaningful markup for a pristine, certified example. Damaged, cleaned, or scratched pieces drop back toward melt.

This is not a rare-date rarity worth tens of thousands. It is a substantial silver asset. Anyone claiming it is worth "a fortune" beyond its silver content plus a collector premium is misleading you.

The specs that matter

Feature	Detail
Denomination	100 Pesos
Year	2013
Metal	Silver
Weight	1,000 g (1 kilo, 32.15 troy oz)
Diameter	110 mm
Edge	Plain (smooth)
Mint	Casa de Moneda de México
Catalog reference	KM#921
Finish	Matte and brilliant (mate-brillo) relief

The design pairs a value-side featuring the coat of arms with the reverse showing the Aztec Sun Stone, often called the Aztec Calendar. The two-tone matte-and-brilliant finish is intentional and part of how you tell a genuine strike from a cheap copy.

Is it rare?

Not in the way most people hope. This belongs to Mexico's modern silver bullion program under the "nuevo peso" (new peso) system, introduced in 1993 after a currency reform that dropped three zeros from the old unit. The one-kilo format is niche and expensive to produce, so mintages are low compared to circulating coins, and that scarcity supports a modest premium. But it is a deliberately issued collector and investor product, not an accidental error or a lost mintage.

The real driver of value here is the silver content first, then condition and completeness (capsule, certificate, box). A perfectly preserved example commands more from serious buyers who want the full presentation set.

Coins people confuse this with

Buyers sometimes mix this up with the Onza Libertad, Mexico's one-ounce silver bullion coin that also shows a national design and trades near melt plus a small premium. The kilo Aztec Calendar is a different animal: 32 times the silver, a much bigger diameter, and a higher collector premium. If you have several "silver Mexican coins," weigh each one. The kilo piece is unmistakable at 1,000 grams and 110 mm across.

How to check what yours is worth

Start with the metal. Weigh it on a jewelry scale. It should read very close to 1,000 grams. Measure the diameter with calipers: 110 mm. If those numbers are off, you may have a fake or a plated copy, and you should stop before paying anyone.

Next, judge condition honestly. Look for scratches, fingerprints, milk spots, and toning under good light. Never clean it. Cleaning silver destroys the surface and cuts the value. A coin still sealed in its original capsule with paperwork is worth more than a loose, handled one.

For a real number, get it graded or appraised. Third-party grading services like NGC and PCGS certify authenticity and assign a grade, which matters when you sell to collectors. For melt confirmation and a quick offer, a verified numismatic dealer will weigh it and quote you on the spot.

How to tell if it's genuine

Weight and diameter are your first defense. Counterfeits almost always miss on one or both, and 32 troy ounces of silver is hard to fake cheaply. Check the relief: genuine strikes have crisp detail and the intended matte-and-brilliant contrast, not flat, uniform surfaces. Be suspicious of any offer priced well below the current silver value. Nobody sells a kilo of real silver at a loss.

Where to sell it

Because this is a precious-metal piece, sell only to someone who will weigh it in front of you and quote against a live silver price. A verified numismatic dealer from the Pesoteca directory will value it on the spot without a middleman markup. For collector-to-collector sales at the best premium, list it in the Pesoteca buy-and-sell forum with clear photos of both faces and the edge. Avoid dumping it to the first buyer on social media, and never ship a kilo of silver before payment clears.

Have a whole box to sort through? Post photos in the Pesoteca forum and let the community help you figure out which pieces are silver and which are worth grading.