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Silver coin guide

Washington Quarter (1932–1964) — ping test & specs

Silver Washington quarters (1932–1964) are the workhorse of junk-silver stacks: 6.25 g of .900 silver at 24.26 mm. The 1965+ clad quarter weighs 5.67 g and rings audibly differently — this reference is the silver coin only.

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

Official specifications

Weight6.25 g
Diameter24.26 mm
Composition.900 silver (90%)

Source: United States Mint. Coin Pinger checks measured weight and diameter against these values.

Expected resonance range

High confidence*
ModeExpected ringRecommended variance
c0d25.49–6.85 kHz±11.1%
c0d312.73–15.77 kHz±10.7%

A genuine Washington Quarter (1932–1964) 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 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.

Small-coin note: at 24.26 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 Washington Quarter (1932–1964) 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 Washington Quarter (1932–1964)

  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.

Washington Quarter (1932–1964) — frequently asked

How much does a Washington Quarter (1932–1964) weigh?

The official specification is 6.25 g in .900 silver (90%) (source: United States Mint). 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 Washington Quarter (1932–1964)?

24.26 mm in diameter, per United States Mint. 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 Washington Quarter (1932–1964) ring at?

Its fundamental (c0d2) vibration mode is computed to ring in the 5.49–6.85 kHz range, with higher modes near 12.73–15.77 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 Washington Quarter (1932–1964) ring slightly off the listed frequencies?

Wear is the biggest factor for the Washington Quarter (1932–1964): 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 Washington Quarter (1932–1964)?

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.

Related silver coins

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The physics of the Washington Quarter (1932–1964) ping

Those 2 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 and 3 nodal diameters, written c0d2 / c0d3. 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 Washington Quarter (1932–1964) spreads 6.25 g of .900 silver (90%) across 24.26 mm — an effective disc thickness of about 1.3 mm once the raised rim and relief are averaged out — which puts its fundamental (c0d2) near 6170 Hz.

An ideal thin disc's modes sit at fixed, geometry-only ratios: 1 : 2.33. 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 : 2.31. 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 ≈2650 Hz instead of 6170 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 →