I came across the Pocket Pinger on last night, and found it quite interesting. The inventor (?) claims you are able to detect real vs fake by using this device. Check out the website link below, he shows a demonstration of the product: Coin Ping Test - Sound Money Metals 2 videos
2022 Silver Britannia does not ping. Should I be worried? - Silver
Can I recognise fake silver coins? - Silver - The Silver Forum
The Pocket Pinger: companion tool for Precious Coin Tester
The Pocket Pinger
The Pocket Pinger + Stack Stick, Coin Ping Test (Black
The Pocket Pinger
New Testing Equipment: The Pocket Pinger - General Precious Metals
The Pocket Pinger
New Testing Equipment: The Pocket Pinger - General Precious Metals
Coin Metal Tester
The Pocket Pinger + Stack Stick, Coin Ping Test (Black
2022 Silver Britannia does not ping. Should I be worried? - Silver