Bullion Test Demo 1.7

This application provides a cost-effective and user-friendly solution for detecting counterfeit bullion coins by analyzing their resonance frequencies.

Resonance frequencies are influenced by the shape and material composition of an object. In instances where a coin's shape and weight conform to that of a genuine silver coin, but the material is found to be different, resonance testing can reveal discrepancies. This method is sometimes referred to as the "ring test" or "ping test."

One significant advantage of this app over traditional manual ring tests is that it does not require the user to possess prior knowledge of how each coin should sound. Moreover, it has the capability to detect resonance frequencies that fall outside the range of human hearing.

A demonstration of how to utilize this app is available in the following video: YouTube Video.

The free version of the application supports three types of coins, with an option to purchase the full version for access to a broader range of coins.

To use this app effectively:

1. To achieve optimal results, perform the test in a quiet environment, as high-frequency sounds from electronic devices may interfere with the assessment.
2. Select the type of bullion coin to be tested from the drop-down menu, noting that only three types are supported in this version.
3. Activate the test by pressing the microphone button.
4. Blue lines will illustrate the anticipated resonance frequencies for the selected coin.
5. Hold the coin steadily near your smartphone's microphone, then gently tap it using your fingernail or a hard object. Avoid using another coin for tapping, as it may skew the results. The necessary sound level will depend on your device's microphone sensitivity; typically, gently tapping with a fingernail suffices.
6. 1. If the sound aligns with the expected resonance frequencies, a green check mark will appear.
   2. If excessive background noise is detected or if the sound does not meet expected frequencies, a red cross will be shown.
   3. Some Android devices may have microphones that only capture frequencies below approximately 10kHz. If two out of three expected frequencies are detected, this will be indicated as "2/3," along with a note about potential device limitations affecting frequency detection.
7. Users may need some practice to produce a clear sound from the coin. The app is sound-activated, allowing for multiple tests if needed.

Required permissions include:

• Record audio: Needed to capture the sound produced by the coin.
• Storage: Required for sharing test results.

Disclaimer: There are no assurances regarding the functionality and accuracy of this app. Various factors may lead to false positive or negative results. This application should be considered a supplementary tool and not a substitute for other verification methods.

A forum thread for discussions and additional information about this app can be found here: Forum Discussion.