1920 Fat Man Dollar PMD Or Otherwise?

Manage to get hold of a subscriber to ping test the coin with the correct 1920 FatMan Dollar Apps. I have no idea what alloy formula can emulate exact ping and pass Sigma for .900 Ag (Sigma doesn't have .89 Ag selection)? I will perform a specific gravity test when I have the necessary apparatus.



In between, the frequency spectrum looks much cleaner compared to when using the wrong Morgan Apps earlier in the thread.

I dismantled an old spoiled Hard Disk Drive to remove the Neodymium magnet inside. Tested on this coin.



I balanced the coin on my finger tip while avoiding direct contact. There isn't any knocking or touching of the magnet against the coin, if there is the coin would dropped from my finger pivot. Moving back and forth the magnet creates a changing magnetic flux to cause the rocking of the coin. Otherwise the coin is not attracted to the magnet.

Diamagnetism is the property of materials that are repelled by a magnetic field, due to the induced magnetic field in the opposite direction.

I do not have a N52 slider. But it rocks because it repels. If it is paramagnetic it will weakly attract e.g. Tungsten. The video clearly show it is not Ferro.

Wish I have access to an XRF metal analyzer to measure and breakdown the elements composition. I don't.

Thanks to your photo illustration. Need to buy a proper N52 to do. Good Night.

Readily found in many sizes.
Something about diamagnetic coins is that the idea is to see if a reaction does or does not happen. If it does not, unlikely the coin is silver. But if it does, it is not proof the coin is silver at all. Other elements can give similar or confusing results such as aluminum and copper. That's why follow-up testing by other means is needed as a next step or two.