Coin Pinger
Acoustic bullion authentication — free, private, on-device
Most-traded coins
The most popular bullion coins to ping test
The world's most-traded bullion coins are also the most-counterfeited — which makes them the coins most worth ping testing. These 12 references cover the staples of every stack: Eagles, Maples, Krugerrands, Britannias, Philharmonics, and the classic Morgan and Peace dollars.
7 silver staples
| Coin | Weight | Diameter | Fineness | c0d2 ring | |
|---|---|---|---|---|---|
| Morgan Dollar | 26.73 g | 38.1 mm | .900 silver | 3.86–4.82 kHz | |
| Peace Dollar | 26.73 g | 38.1 mm | .900 silver | 3.86–4.82 kHz | |
| Silver American Eagle 1 oz | 31.103 g | 40.6 mm | .999 | 3.52–4.00 kHz | |
| Silver Britannia 1 oz | 31.21 g | 38.61 mm | .999 | 4.31–4.91 kHz | |
| Silver Krugerrand 1 oz | 31.107 g | 38.7 mm | .999 | 4.26–4.85 kHz | |
| Silver Maple Leaf 1 oz | 31.103 g | 38 mm | .9999 | 4.58–5.21 kHz | |
| Silver Philharmonic 1 oz | 31.103 g | 37 mm | .999 | 5.10–5.80 kHz |
5 gold staples
| Coin | Weight | Diameter | Fineness | c0d2 ring | |
|---|---|---|---|---|---|
| Gold American Eagle 1 oz | 33.931 g | 32.7 mm | .9167 gold | 4.34–5.00 kHz | |
| Gold Britannia 1 oz | 31.104 g | 32.69 mm | .9999 | 3.28–3.94 kHz | |
| Gold Buffalo 1 oz | 31.108 g | 32.7 mm | .9999 | 3.28–3.93 kHz | |
| Gold Krugerrand 1 oz | 33.93 g | 32.77 mm | .9167 gold | 4.30–4.96 kHz | |
| Gold Maple Leaf 1 oz | 31.103 g | 30 mm | .9999 | 4.62–5.55 kHz |
Every frequency is computed from first-principles free-plate physics using the mint's published mass and diameter — see the methodology. Each coin's page lists all vibration modes, tolerances, and a physics explainer.
Coin not listed?
Compute the expected ring for any coin from its mass, diameter, and metal with the resonance calculator — or calibrate your own genuine coin directly in the app.
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