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Silver Libertad 2 oz — ping test & specs

The 2 oz Silver Libertad spreads 62.2 g across a broad 48 mm flan — a low, sonorous ring distinct from any 1 oz coin.

Opens the free tester with this coin preselected — audio never leaves your device.

Official specifications

Weight62.2 g
Diameter48 mm
Composition.999 fine silver

Source: Casa de Moneda de México (Banco de México). Coin Pinger checks measured weight and diameter against these values.

Expected resonance range

High confidence*
ModeExpected ringRecommended variance
c0d23.60–4.09 kHz±6.4%
c0d38.34–9.34 kHz±5.7%
c0d414.46–16.21 kHz±5.7%

A genuine Silver Libertad 2 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 high-confidence tag reflects how well-established this metal's constants are: Computed from well-established silver elastic constants and cross-checked against same-size sibling coins. 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 Silver Libertad 2 oz is genuine but it won't match? Send us its ring — we'll dig in and improve the reference.

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How to ping test a Silver Libertad 2 oz

  1. 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.
  2. Tap — strike the edge with a striker near the microphone.
  3. Read the verdict — MATCH or NO MATCH against the peaks above, plus weight and size checks.

Silver Libertad 2 oz — frequently asked

How much does a Silver Libertad 2 oz weigh?

The official specification is 62.2 g in .999 fine silver (source: Casa de Moneda de México (Banco de México)). Coin Pinger's weight check allows ±0.3 g by default.

What size is a Silver Libertad 2 oz?

48 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 Silver Libertad 2 oz ring at?

Its fundamental (c0d2) vibration mode is computed to ring in the 3.60–4.09 kHz range, with higher modes near 8.34–9.34 kHz and 14.46–16.21 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 Silver Libertad 2 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 Silver Libertad 2 oz in the app.

Does ping testing damage a Silver Libertad 2 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.

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The physics of the Silver Libertad 2 oz ping

Those 3 peaks aren't random. When you strike the coin it flexes as a free disc in fixed patterns called vibration modes — 0 nodal circles with 2, 3 and 4 nodal diameters, written c0d2 / c0d3 / c0d4. Each pattern rings at one frequency.

Where those frequencies land is set by the coin's geometry and metal. For a thin disc, frequency ∝ (thickness ÷ diameter²) × √(stiffness ÷ density). This Silver Libertad 2 oz spreads 62.2 g of .999 fine silver across 48 mm — an effective disc thickness of about 3.3 mm once the raised rim and relief are averaged out — which puts its fundamental (c0d2) near 3845 Hz.

An ideal thin disc's modes sit at fixed, geometry-only ratios: 1 : 2.33 : 4.11. A real coin isn't infinitely thin — shear in the metal drags the higher modes slightly below the ideal — so this coin's computed reference lands at 1 : 2.30 : 3.99. Spacing near those ratios is the fingerprint of a struck disc, and Coin Pinger rejects taps that don't fit it (keys, glass, a coin lying on a hard surface).

And it's why a fake can't hide: change the metal and √(E/ρ) changes, so every mode moves. Struck in lead or a plated base metal instead, the ring would land far lower and die out with a dull, short thud — its c0d2 would land near ≈1700 Hz instead of 3845 Hz. Density can fool a scale; the ring can't be faked without the right metal.

We publish this as a High confidence reference. Computed from well-established silver elastic constants and cross-checked against same-size sibling coins.

Free-plate modes per A. W. Leissa, Vibration of Plates, NASA SP-160 (1969, public domain). See how we measure them →