So long as counterfeiters can produce fakes for less than the cost of authentic silver coins, and so long as man’s nature is what it is, there will always be phony coins on the market. While the comparatively low price of the metal makes silver coins less susceptible to counterfeiting than gold, fraudsters can still make a bundle by passing off fake silver coins, minted with inexpensive base metals, onto unsuspecting buyers.
So how do you tell if a coin is genuine silver or a fake? There are several tests to which you can subject your coins. Some of them are potentially (or definitely) destructive, so they shouldn’t be used with collectible coins. Some tests are simple; others are complicated and require special tools. But no matter your budget, you should find at least some of the sixteen tests described below useful. Some of the tests are even fun!
The ‘Ping’ Test
This most basic of tests is surprisingly effective: Simply drop a (non-numismatic) silver coin that you know to be real on a table and listen for the distinctive “ping” sound — this is very difficult to fake. The ping test doesn’t guarantee you’ll spot every counterfeit coin, but it should be the first test to which you subject any suspect coins.
The ping test runs the risk of inflicting “micro-abrasions” on coins, which is why it should only be used with non-numismatic coins.
The Ice Test
This is a fun test: Take two ice cubes and place them on (1) a silver coin you know to be real, and (2) a coin you suspect may be a fake. If the ice on the suspect coin melts much slower than the ice on the silver coin, you’ll know you have a fake on your hands.
Silver is the most heat-conductive metal in existence, so ice melts very quickly whenever it comes into contact with it. This effect is especially noticeable when you compare how fast ice melts on silver versus how slowly it melts on a metal pan. But in my own tests, I was surprised to see how quickly ice melted on top of a cheap-metal challenge coin or even a modern U.S. quarter (with no silver content) — definitely not as fast as the silver coin, but much faster than the metal pan. Keep this in mind — and keep an authentic silver coin on hand for side-by-side tests.
Magnetic Tests (2)
If a supposedly silver coin sticks to a magnet, you can guarantee that it’s a fake. Of course, many fakes will pass the simple magnetic test — zinc, for instance, is non-magnetic — but silver isn’t non-magnetic, it’s diamagnetic: This means it is repelled by magnetic fields.
Silver’s diamagnetism makes the magnetic-slide test very effective at spotting fakes. In the video linked below, a man has constructed a slide made out of magnets, which he uses to slide down fake and real silver items. The fakes fall down the slide with no resistance, while the real items slide down much more slowly.
It should be noted that copper and lead are also diamagnetic (although their diamagnetism isn’t as strong as silver’s). As the author of the video linked above notes, a silver-plated coin with a copper core would likely pass the magnetic slide test.
Visual Tests (3)
Visual tests can easily spot egregious fakes, especially with the aid of an authentic coin for comparison’s sake. The coin’s markings, edge finishes, and relief (i.e., the height of its images relative to the coin’s surface) should closely match the genuine article.
A jeweler’s loupe is a great tool for visual inspections, but a magnifying glass can suffice in a pinch. Using 10x magnification or greater, you should be sure to check the edges of the coin for reeding (i.e., its grooves). The absence of reeds virtually guarantees the coin is a fake, since non-reeded authentics are rare and valuable errors.
Of course, not all eyes are created (nor cultivated and maintained) equally: An experienced jeweler will be able to spot a fake much more reliably than you, and even experienced jewelers can be tricked. Thus, visual tests can eliminate fakes but they cannot guarantee authenticity.
Measurement Tests (6)
Real silver coins have precise dimensions and a consistent weight: Any coin that is too big or too small, too light or too heavy, is obviously a fake. You can measure the weight, thickness, diameter, and shape of four different coins (including the American Silver Eagle) using a tool called the Fisch. Simple weight can be determined using any scale with accuracy to at least 0.1 grams (scales with accuracy to two or three decimal places are preferable).
Of course, it’s far from impossible for sophisticated counterfeiters to get the dimensions and weight of their coins right, so — just as with visual tests — basic measurement tests can catch some but not all fakes. But what about advanced measurement tests?
The specific gravity test is a good one: It involves weighing a silver coin submerged in water, and dividing that weight by the coin’s dry weight. The result, which is the coin’s specific gravity (i.e., relative density compared to water), should be very close to 10.49 (the specific gravity of pure silver). Note that you’ll need to suspend the silver underwater using a piece of string — in order for the test to work, the silver can’t be touching any part of the water container. See the video linked below:
Another advanced test is the ultrasonic thickness test. You’ll need a $185 ultrasonic thickness gauge to conduct this one, and although it’s highly accurate for thick bars, it doesn’t work as well for coins. See the video linked below:
There are two more advanced measurement tests to consider:
- XRF analysis, which uses x-ray fluorescence to detect precious metals and other content; and
- Metalytics, which involves sending electromagnetic waves through metal to confirm its composition.
XRF analyzers can cost close to $2,000 (or more), while the Sigma Metalytics Precious Metals Verifier starts at $699. See the video of the latter linked below:
Destructive Tests (3)
I’ve saved the most serious and accurate tests for last:
- The bleach test
- The acid test
- The fire-assay test
All three tests are destructive and should not be used with numismatic coins.
The bleach test is very simple: You just expose your coin to a drop of bleach (i.e., Clorox). Real silver tarnishes very quickly, which means it turns black when exposed to oxidizing chemicals.
The acid test requires an acid testing kit. A silver coin will stay a certain color (silver-blueish), while fake silver will turn a different color depending on the metal used to counterfeit the coin.
Both the bleach test and the acid test have difficulty sniffing out silver-plated coins with cheap metal cores. For these, nothing beats a fire assay — but this ultimately destructive test isn’t very practical. Indeed, its inclusion on this list serves to underscore the relative unreliability of the other fifteen tests.
Combine Tests for Greater Confidence
It’s easy for counterfeiters to pass some tests at the expense of others — but it’s very difficult to pass several of the tests with the same fake coin.
- Start out with the simple “ping” test.
- Conduct an ice test with a genuine silver coin, the suspected fake, and several known fakes (or non-silver coins).
- Make sure the suspected fake isn’t magnetic — and if you have a magnetic slide, subject the suspected fake to the magnetic-slide test.
- Examine the suspected fake with a jeweler’s loupe or magnifying glass, paying especially close attention to its reeds (or lack thereof).
- Weigh the coin using a scale accurate up to at least 0.1 grams — 0.01- or 0.001- gram accuracy is preferred. Use a Fisch if you have one.
If you’re not convinced of the coin’s authenticity at this point, consider using the bleach or acid tests — or investing in higher-grade (and more expensive) equipment.
In general, people don’t apply these tests to coins before they buy them, but only afterward. For person-to-person transactions, some of the tests are appropriate, but many are not. For online deals, all of the tests are impossible — which underscores the importance of transacting with reputable dealers.