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Gold coin guide
Austrian 100 Corona — ping test & specs
The Austrian 100 Corona is a .900 gold restrike dated 1915, sold at bullion value with 30.49 g of fine gold. Its copper alloy and 37 mm size give it a lower ring than pure-gold coins.
Opens the free tester with this coin preselected — audio never leaves your device.
Official specifications
| Weight | 33.875 g |
| Diameter | 37 mm |
| Thickness | 2.3 mm |
| Composition | .900 gold (90%) |
Source: Austrian Mint (restrike). Coin Pinger checks measured weight and diameter against these values.
Expected resonance range
Good confidence*| Mode | Expected ring | Recommended variance |
|---|---|---|
| c0d2 | 2.52–3.17 kHz | ±11.5% |
| c0d3 | 5.85–7.30 kHz | ±11.1% |
| c0d4 | 10.24–12.79 kHz | ±11.1% |
A genuine Austrian 100 Corona 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). 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.
* These are computed guidance ranges. Certain your Austrian 100 Corona 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 Austrian 100 Corona
- 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.