Magnet, ice, ping, weight, size and acid tests for silver coins and bars: how each works, what it can and cannot prove, and when to get an electronic test or a second opinion.
Short answer: no single home test proves that silver is real, but a few together make a strong case. Check weight, diameter and thickness against the official specifications first. Then use the magnet, ice and ping tests as screens, and use a electronic tester or XRF scan from a dealer for anything valuable. The best protection is buying from reputable sellers and keeping the receipt.
| Test | Reliability | Harmless? | What it catches |
|---|---|---|---|
| 1. Weight and dimensions | High | Yes | Wrong metal, wrong size |
| 2. Electronic conductivity tester | High | Yes | Many non-silver metals |
| 3. XRF scan at a dealer | Very high | Yes | Composition, plating |
| 4. Ice test | Medium | Yes | Low-conductivity fakes |
| 5. Magnet test | Low-medium | Yes | Iron or steel cores |
| 6. Ping test | Low | Yes | Dull-sounding fakes |
| 7. Acid test | Medium | No | Plating and base metal |
Every bullion coin has a published weight, diameter and thickness. Weigh the coin on a scale accurate to 0.01 g and measure it with digital calipers. A one-ounce silver coin should weigh about 31.1 g; a counterfeit made from a cheaper metal has trouble matching weight, diameter and thickness at once. See how to weigh accurately and the guide to weight tolerances. You can also check density: weight divided by volume should be close to silver's 10.49 g per cubic centimetre.
Devices such as electrical conductivity testers measure how the metal conducts electricity, which differs between silver and common substitutes. They are non-destructive and quick. They can be fooled by some clever fakes, so treat a pass as strong evidence, not proof.
X-ray fluorescence analysers read the elements in the surface of the metal. Many coin shops and dealers have one and will scan an item on request. It is the most reliable non-destructive check, though it reads only the surface, so a thick plating over a different core can mislead. For high-value bars, ask whether the dealer uses ultrasonic testing too.
Silver conducts heat better than any other metal. Put an ice cube on a silver coin and one on a coin of another metal, and the ice on the silver melts noticeably faster, often within seconds. It is a fun and harmless screen, but copper conducts heat well too, so a fast melt does not confirm silver.
Silver is not magnetic, so a coin that sticks to a magnet is not silver. Use a strong neodymium magnet. If you tilt it over a real silver coin, the coin will cause the magnet to slide slowly because of eddy currents, a nice sign. Many fakes, however, are made of non-magnetic metals, so passing means little.
Balance a coin on your fingertip and tap it with another coin. Silver gives a clear, long ringing sound. Experience matters, and some fakes ring convincingly, so use it only as a quick screen. Never tap valuable collector coins, as it can damage them.
Acid kits put a drop on a scratch or file mark and the colour reaction shows silver content. They are best for scrap silver and unmarked items. The test leaves a mark, so don't use it on coins you plan to sell as coins.
The best protection is the source. Buy from established dealers, not anonymous sellers, and be suspicious of prices below spot. Our guides on spotting counterfeits and checking a dealer is legitimate go further. Learn what counterfeit bullion looks like, and keep a photo, weight and receipt for each piece in BullionKeeper, so you can prove what you bought and where.
Start with weight and dimensions, since these are hard to fake together. A coin that matches the published weight, diameter and thickness is far more likely to be genuine. Follow with the magnet and ice tests as quick screens.
No. Silver is not magnetic, so a coin that sticks strongly to a magnet is not silver. But many fakes are also non-magnetic, so passing the test proves little.
Silver conducts heat better than any other metal, so an ice cube placed on a silver coin melts noticeably faster than on most fakes. It is a useful screen, but copper and some alloys also conduct heat well, so it is not proof.
Acid testing leaves a mark on the surface and can reduce the value of a coin. It suits scrap and unmarked items, but should not be used on collector coins or anything you plan to sell as a coin.
Reputable coin shops and dealers can test with electronic testers or X-ray fluorescence, often for a small fee or free if you sell to them. Buy from reputable sources and keep receipts to reduce the chance of a fake in the first place.
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