With thousands of counterfeit/fake/replica coins coming out right now, it would be practical for the collector to ensure that they are purchasing the authentic ones. A fake silver coin can be quickly detected using a neodymium rare earth magnet.
Hold the coin at an angle of 45 degrees, place the magnet at the top of the coin and then let it slide.
• If the magnet sticks to the coin. (Silver is basically non-magnetic)
• If the magnet slides straight right off the coin.
• If the magnet slowly slides down the coin.
Magnet passing to a non-magnetic conductor creates eddy currents. The intense magnetic field, created by the rare earth magnet, induces a current on the coin, creating an opposing magnetic field. The two fight it out, slowing the slide. Not magic of course just magnets.
• Sliding magnets can cause micro abrasion on the coin surface. Use plastic coin pockets if neccesary.
• Silver plated metals will repond and might have the same effect. Skills and experience are still needed.
Here are some videos… Enjoy…
Extra on Eddy Currents: