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Gold coin guide
Gold Libertad 1 oz — ping test & specs
Mexico's 1 oz Gold Libertad is unusually wide for its weight (34.5 mm), which drops its ring below most 1 oz gold coins — a distinctive acoustic signature.
Opens the free tester with this coin preselected — audio never leaves your device.
Official specifications
| Weight | 31.1 g |
| Diameter | 34.5 mm |
| Composition | .999 fine gold |
Source: Casa de Moneda de México (Banco de México). Coin Pinger checks measured weight and diameter against these values.
Expected resonance range
Provisional confidence*| Mode | Expected ring | Recommended variance |
|---|---|---|
| c0d2 | 2.65–3.17 kHz | ±9.1% |
| c0d3 | 6.15–7.30 kHz | ±8.5% |
| c0d4 | 10.76–12.76 kHz | ±8.5% |
A genuine Gold Libertad 1 oz rings within these ranges at its c0d2/c0d3/c0d4 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). The higher modes also carry a small thick-plate centre correction, since a real coin is not infinitely thin. The provisional-confidence tag reflects how well-established this metal's constants are: Computed from .9999 gold's annealed modulus — the least-certain material input, so the band is widened and this reference is best confirmed by calibrating a coin you know is genuine. 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.
* These are computed guidance ranges. Certain your Gold Libertad 1 oz 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 Gold Libertad 1 oz
- 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.
Gold Libertad 1 oz — frequently asked
How much does a Gold Libertad 1 oz weigh?
The official specification is 31.1 g in .999 fine gold (source: Casa de Moneda de México (Banco de México)). Coin Pinger's weight check allows ±0.3 g by default.
What size is a Gold Libertad 1 oz?
34.5 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 Gold Libertad 1 oz ring at?
Its fundamental (c0d2) vibration mode is computed to ring in the 2.65–3.17 kHz range, with higher modes near 6.15–7.30 kHz and 10.76–12.76 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 Gold Libertad 1 oz ring slightly off the listed frequencies?
Phone-mic capture moves a genuine peak a few percent tap-to-tap — strike point, holding pressure, and the microphone's own response all matter. Temperature and normal minting tolerance add under 1%. The published band already allows for all of this; for a tighter reference, calibrate your own genuine Gold Libertad 1 oz in the app.
Does ping testing damage a Gold Libertad 1 oz?
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.