Coin Pinger
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Gold coin guide
Gold Kangaroo 1/10 oz — ping test & specs
The tenth-ounce Gold Kangaroo is a 16.6 mm .9999 Perth Mint coin with year-to-year striking variation — small, high-pitched, and band-widened for both size and variability.
Opens the free tester with this coin preselected — audio never leaves your device.
Official specifications
| Weight | 3.111 g |
| Diameter | 16.6 mm |
| Composition | .9999 fine gold |
Source: Perth Mint. Coin Pinger checks measured weight and diameter against these values.
Expected resonance range
Provisional confidence*| Mode | Expected ring | Recommended variance |
|---|---|---|
| c0d2 | 4.85–6.00 kHz | ±10.6% |
| c0d3 | 11.28–13.85 kHz | ±10.2% |
A genuine Gold Kangaroo 1/10 oz 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 the issue is struck at slightly varying thickness across years. 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.
Small-coin note: at 16.6 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 Gold Kangaroo 1/10 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 Kangaroo 1/10 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 Kangaroo 1/10 oz — frequently asked
How much does a Gold Kangaroo 1/10 oz weigh?
The official specification is 3.111 g in .9999 fine gold (source: Perth Mint). Coin Pinger's weight check allows ±0.3 g by default.
What size is a Gold Kangaroo 1/10 oz?
16.6 mm in diameter, per Perth 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 Gold Kangaroo 1/10 oz ring at?
Its fundamental (c0d2) vibration mode is computed to ring in the 4.85–6.00 kHz range, with higher modes near 11.28–13.85 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 Kangaroo 1/10 oz ring slightly off the listed frequencies?
The Gold Kangaroo 1/10 oz is struck at slightly varying thickness across years, and frequency scales directly with thickness — so genuine specimens from different years ring at measurably different pitches. Phone-mic capture adds a few percent more tap-to-tap spread. That's why this reference band is wider than average.
Does ping testing damage a Gold Kangaroo 1/10 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.