Blog 7: Gold and Silver testing using a Magnetic Pendulum



An exclusive product developed and patented at, the EON Gold Coin Cradle means you never feel uncertain about your precious metals again. It places the power in your hands to measure, weight and test the conductivity of your coin. These three tests are adequate to authenticate any precious metal coin. The cradle allows you to experience your precious metals in a way that hasn't been available before. Precious metals are tactile, they are beautiful, and they have intriguing characteristics.

Weight: Gold is one of the heaviest (most dense) metals, with only a few rare metals being heavier. Weighing a coin and checking its weight against its specified weight is the first essential step in verifying your coin. Coins may weigh slightly more than the specified weight, but should never weigh less than the specified weight. We supply a sensitive scale that will measure your coins weight down to .001 of a gram. much more than you need.  Once you have checked your coins weight against the specified weight on our website you can move on to the next step.

 Gold Coin Weight and Diameter Testing

Measurement: It is important your coin has the right dimensions, Check its Diameter and its thickness with our coin slider. Simply place the coin in the slider and when checking the diameter read from the right side of the coin, this will tell your the diameter of your coin. Gold Coin Diameter Testing

To measure the thickness slot the coin between the coin slider and the wall of the gradient, and read from the arrow of the coin slider. Both the diameter and the thickness of you coin will be in mm.

 Gold Coin thickness measurement


Conductivity: This is the fun part of the test, you have now established your coin has the right density. The only way a counterfeit coin can be made to have the right density is by either using tungsten in the centre of the core which a different conductivity than would be expected from your coin. Or by mixing a higher and lower density metals which will also give a different conductivity reading.

Silver and Gold are the first and third most conductive metals, So we can measure the conductivity by measuring the slowing effect they have on our magnetic pendulum. The coins will slow down the pendulum as when the pendulum passes over the coins an Eddy Current is created, damping the movement of the pendulum.

Simply place your coin in the vice, release the pendulum and read from the dial. Smaller coins than the One Ounce Coins can be measured by lowering the pendulum using the calibration spacer provided. The Magic of Science in your hands, we hope you enjoy it as much as we did making it!.

Testing the purity of a small gold coin


The dial starts out from the expected purity of the coin, so if a coin like the Austrian Philharmonic is being tested then the dial will be set to 99,9% pure. Once the test is run the dial will be expected to land in the pass zone at 12 O'clock if the coin is authentic.

Gold Purity Dial


The product uses the unique properties of gold to test in a completely mechanical way. it is expected to retail for around 400 Euro. If you would like to be put on the waiting list please contact us via the contact form.

The final product may look slightly different from the product render shown here as the final engineering specifications are being finalised.

Let us know what you think in the comments below!

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Blog 8: What are the Properties of Gold?

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