Coin Pinger
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Gold coin guide
Mexican 5 Pesos — ping test & specs
The 5 pesos carries 4.17 g of .900 gold at 19 mm — a small, bright ringer at the edge of phone-mic testing.
Opens the free tester with this coin preselected — audio never leaves your device.
Official specifications
| Weight | 4.1666 g |
| Diameter | 19 mm |
| Composition | .900 gold (90%) |
Source: Casa de Moneda de México (Banco de México). Coin Pinger checks measured weight and diameter against these values.
Expected resonance range
Good confidence*| Mode | Expected ring | Recommended variance |
|---|---|---|
| c0d2 | 4.45–5.61 kHz | ±11.5% |
| c0d3 | 10.35–12.94 kHz | ±11.1% |
A genuine Mexican 5 Pesos rings within these ranges at its c0d2/c0d3 vibration modes, fixed by its size and metal. The recommended variance is how far a genuine specimen's ring can sit from each center — built up in quadrature from real manufacturing tolerance and temperature (under 1%), phone-mic capture reproducibility (≈4%), an extra allowance on the fundamental for minting-asymmetry splitting, and a per-metal model-uncertainty term (largest for .9999 gold, whose modulus is least certain). This coin's band is widened further because circulated 90%-silver classics lose mass and edge crispness with wear, spreading their ring. The higher modes also carry a small thick-plate centre correction, since a real coin is not infinitely thin. The good-confidence tag reflects how well-established this metal's constants are: Computed from 22k-gold alloy constants, which are slightly less certain than silver; the band is set accordingly. These are guidance bands, not exact values — see the methodology for the exact formula, or calibrate your own coin in the app for a specimen-exact reference and tighten each peak per coin.
Small-coin note: at 19 mm this coin is below the ≥25 mm sweet spot — its ring is higher-pitched, shorter, and quieter than a full-size coin's, and only two of its modes stay under the 20 kHz phone-mic ceiling. Tap close to the microphone in a quiet room, expect more retries, and lean harder on the weight and diameter checks.
* These are computed guidance ranges. Certain your Mexican 5 Pesos is genuine but it won't match? Send us its ring — we'll dig in and improve the reference.
🎙 Submit sample pingsHow to ping test a Mexican 5 Pesos
- Hold — grip the coin by its center (a nodal point) in a coin ping-test holder so the rim rings freely; a fingertip at the center is a last resort.
- Tap — strike the edge with a striker near the microphone.
- Read the verdict — MATCH or NO MATCH against the peaks above, plus weight and size checks.
Mexican 5 Pesos — frequently asked
How much does a Mexican 5 Pesos weigh?
The official specification is 4.1666 g in .900 gold (90%) (source: Casa de Moneda de México (Banco de México)). Coin Pinger's weight check allows ±0.3 g by default. Circulated specimens lose a little mass to wear, so weigh toward the low side of that window.
What size is a Mexican 5 Pesos?
19 mm in diameter, per Casa de Moneda de México (Banco de México). Note the average disc thickness is less than the rim caliper reading — the raised rim and relief concentrate metal at the edge.
What frequency does a genuine Mexican 5 Pesos ring at?
Its fundamental (c0d2) vibration mode is computed to ring in the 4.45–5.61 kHz range, with higher modes near 10.35–12.94 kHz. These are first-principles physics computations from the coin's published mass, diameter, and metal — not measurements of sample coins.
Why does my genuine Mexican 5 Pesos ring slightly off the listed frequencies?
Wear is the biggest factor for the Mexican 5 Pesos: circulated 90%-silver classics lose mass and edge crispness, which spreads the ring across specimens. On top of that, phone-mic capture moves a genuine peak a few percent tap-to-tap (strike point, how you hold it, the mic itself). That's why this reference band is wider than a modern bullion coin's.
Does ping testing damage a Mexican 5 Pesos?
No — the test needs only a light tap on the edge with a non-marring striker (a wooden pencil or plastic stylus works well), far gentler than normal handling. Hold the coin at its center so the rim can ring freely.