Counterfeit Silver: How to Spec-Check Coins and Bars

Counterfeit silver is rarer than counterfeit gold — the metal is cheaper, so the economics of faking it are weaker — but it absolutely exists, and the quality of fakes has improved sharply in the last decade. Tungsten-cored bars, lead-cored coins, silver-plated brass blanks, and convincing copies of popular bullion coins all turn up on secondary markets. The good news is that real silver has a specific combination of physical properties that no economically sensible substitute can match. A handful of cheap tests, done in sequence, will catch the overwhelming majority of fakes.

This page is a practical checklist. None of these tests alone is conclusive; together they are very hard to fool.

Why silver is testable in a way many metals are not

Silver has unusual physical properties: very high density (10.49 g/cm³), distinctive ringing acoustics, no magnetism whatsoever, very high electrical and thermal conductivity, and extremely low magnetic susceptibility (it actually exhibits weak diamagnetism). These properties are difficult to mimic with any cheaper metal or combination of metals. A counterfeit can imitate one or two of them, but matching all of them simultaneously costs more than the silver content is worth.

Test 1: dimensions and weight

The first and most powerful test is also the simplest. Every legitimate bullion coin and most bars have published, exact dimensions — diameter, thickness, weight — set by the issuing mint or refiner and held to tight tolerances. A fake at a different density (which is most fakes) cannot match all three numbers at once.

For coins, look up the specifications from the mint's own website: a 1oz American Silver Eagle is 40.6 mm diameter, 2.98 mm thick, 31.103 g weight. A 1oz Canadian Silver Maple Leaf is 38 mm diameter, 3.29 mm thick, 31.103 g weight. Use a digital caliper (a $20 item is fine for this) and a precision scale with at least 0.01 g resolution. If diameter, thickness, and weight all match published specs to within manufacturing tolerance, the coin is overwhelmingly likely to be the metal it claims to be — there is no cheaper material with the same density that fits in the same volume to the same weight.

For bars, the tolerance on dimensions is wider, but weight is still tight. A 10oz cast bar should weigh 311.03 g; an out-of-tolerance reading is a red flag.

Test 2: the magnet test

Silver is non-magnetic. A strong rare-earth magnet (a small neodymium magnet) brought close to a silver coin or bar will not stick at all. Two useful variants:

Direct attraction test: place the magnet on the coin. If it sticks, the coin contains ferromagnetic material — iron, nickel, or steel — and is not silver.
Slide test: tilt a silver bar at about 45 degrees, place a strong magnet on its surface, and let it slide. On real silver, the magnet slides slowly, almost reluctantly, because of an eddy-current effect that genuine silver produces. On most fakes, the magnet either sticks or slides freely without resistance.

The slide test is the most informative single test for bars, particularly larger ones, and is hard to fake without using a metal of similar electrical conductivity to silver — of which there are very few candidates, none cheap.

Test 3: the ping test

Silver, especially pure silver, has an unusually long, high, and clear ringing tone when struck. Balance a coin on a fingertip and tap its edge with another coin. Real silver produces a sustained bell-like ring; copper-cored or steel-cored fakes produce a short, dull thud. Various phone apps will analyse the ring and compare it against a library of known coin signatures, and they are surprisingly accurate for genuine bullion coins.

The ping test is less useful on bars (geometry kills the ring) and on smaller coins (where the tone is shorter), but on a 1oz coin it is reliable enough to catch most casual fakes immediately.

Test 4: specific gravity

If a piece passes dimensions, weight, and magnet but you still have doubts — particularly for an unmarked or odd-format item — specific gravity is the closest thing to a definitive test you can do at home. Silver's specific gravity is 10.49 (its density relative to water).

The setup is cheap. You need a digital scale that can take a hanging weight, a glass of water, and a piece of thread. Weigh the item dry, then weigh it suspended in the water (not touching the sides or bottom of the glass). The specific gravity is the dry weight divided by the difference between the dry weight and the wet weight. For sterling, the result should be about 10.36 (slightly lower than pure silver because of the copper alloy); for .999 fine bullion, about 10.49.

Tungsten-cored fakes are the one substitute that can match silver's density — tungsten is much denser, so a tungsten core surrounded by silver can be tuned to match. But tungsten is far more common in gold counterfeits than silver, because the economics of a tungsten-silver fake are poor.

Test 5: ultrasound thickness gauges

For larger bars, an ultrasound thickness gauge is the gold-standard amateur test. The device sends a pulse through the metal and measures the time it takes to return, which depends on the metal's specific acoustic properties. Real silver produces one set of timings; tungsten, lead, or layered fakes produce a different set or visible internal echoes.

Dedicated devices (the Sigma Metalytics Precious Metal Verifier is a well-known example) cost a few hundred dollars and are popular with serious collectors and dealers. They are overkill for occasional buyers but worth considering for anyone holding a meaningful position in larger bars.

What to watch for in the market

Counterfeits cluster around predictable products and channels:

Bullion coins from popular mints — Silver Eagles, Maple Leafs, Britannias, Pandas — are the most-faked products because they have the largest secondary market.
Loose flat bars in 10oz and 100oz sizes, especially generic or unbranded ones, are more often counterfeited than coins because there is more silver per unit and surface detail is simpler.
Online auction listings priced suspiciously below market — particularly on peer-to-peer marketplaces — are a far higher-risk channel than reputable dealers.
Pieces in obviously generic packaging or unsealed assay cards warrant extra scrutiny. Sealed, tamper-evident assay cards from named refiners are not a guarantee, but they raise the bar significantly.

The simplest practical workflow

For most retail buyers, this routine catches almost everything:

Buy from a dealer with a long, verifiable trading history (covered in how to buy physical silver).
When the item arrives, weigh it on a 0.01 g scale and measure it with a caliper. Compare to published mint specifications.
Run a magnet slide test, especially for any bar above a few ounces.
Ping-test 1oz coins.
For anything that does not feel right, run a specific-gravity test before doing anything else with the piece.

If a piece fails any of these tests, do not melt it, do not on-sell it, and do not throw it away. Photograph it, document where you bought it, and contact the dealer. Most reputable dealers will replace or refund a counterfeit shipment without argument, and have an interest in tracing the source.

What this means for storage and resale

Two practical implications follow from the counterfeit landscape. First, sealed and serial-numbered products from named refiners are easier to resell at full price than loose, anonymous bars, because the next buyer faces the same authentication problem you did. Second, if you are storing a meaningful position, keeping the original packaging, the original invoices, and any assay documentation matters — the chain of custody is part of the resale value. The storage article covers this in more detail, especially around allocated vaulting where chain of custody is built into the service.

This article is for informational and educational purposes only and is not investment or appraisal advice. If a piece's authenticity matters financially, professional assay is the only definitive answer. See our full Disclaimer.