Sound-Based Coin Authentication: Looking Lor Beta-Testers

I use the acoustic method all the time for coins submitted to The Black Cabinet. Freeware programs like Audacity and a few others currently support the waveform analysis charts necessary to track harmonics and resonance, but when dealing with coins that have a certain amount of wear or patina on them, things need to be adjusted on the fly.

If this is something that can be distilled down to a smartphone, that would be useful.

The link to The Black Cabinet's in my signature. It's a growing collection and database of counterfeit American coins that are currently in circulation (either among collectors and dealers or as current money).

I don't have any frequencies and maps recorded for posterity. I more often than not test genuine pieces of similar wear side-by-side with submissions and compare fingerprints when other details are inconclusive. The bulk of what crosses my desk are silver dollars, but over the course of an average year I tend to see fake gold pieces, pennies, and halves, too. Just last month I had a fairly convincing St. Gaudens $20 fake, but the weight was so light that I didn't need to check it for resonance to confirm. :-)