GoldScreenPen

The GoldScreenSensor and the GoldScreenPen measure the conductivity of your precious metal object using eddy current testing. In this process, the coil of the respective device induces a magnetic field that generates eddy currents within the object. This allows the conductivity to be determined, which the testing device displays in megasiemens per meter. Each precious metal has a specific conductivity, which is why any impurity would be immediately detected during a measurement. If a precious metal is alloyed with another metal or has a core made of a foreign metal, our devices will indicate this by comparing the target value with the actual value.

The GoldScreenSensor or the GoldScreenPen are worthwhile investments if you enjoy buying coins and bars from private individuals or want to reliably verify your inventory. Thanks to the devices’ unique functionality, you can protect yourself from fraudsters. Even with limited technical knowledge, our devices are easy to use and the results are simple to interpret. Warning: If you encounter a counterfeit, you not only risk significant financial losses—if you resell the counterfeit gold, whether knowingly or unknowingly, you may also be subject to criminal prosecution!

When taking measurements, it is important not to measure at just one point, but to always take measurements at multiple points on the object during testing. In addition, be careful not to press down on the tip of the GoldScreenPen—simply rest it on the surface. Otherwise, the GoldScreenPen may end up measuring its own metal tip as well. To obtain an accurate measurement, the measuring tip must rest completely on the test object and must not be in only partial contact; otherwise, the device will measure air as well, which can distort the result. For extremely small or finely detailed pieces, a definitive result cannot be provided. It is also important to consider the size and thickness of the object; if the test piece is too large, the GoldScreenPen may not be able to identify all counterfeits because the penetration depth could be too shallow. Therefore, please use the GoldScreenPen only for bars and coins weighing up to 1 ounce. Furthermore, you should use at least one additional measurement method (e.g., a vernier caliper and precision scale).

No. The GoldScreenPen measures conductivity and is therefore ideal for detecting counterfeit coins, bars, or silverware. 

Alloys and the exact karat weight of jewelry can be measured using the CaratScreenPen.

For some new fine gold bullion coins (e.g., 2021 Kangaroo, 2021 Lunar Series III), the measured values are at the upper end of the spectrum (usually 46 to 48.5 MS/m). As a result, the conductivity of some coins is displayed as too high on the GoldScreenSensor, even though they are genuine. This is likely due to a new type of ultra-thin coating on the coins, which is intended to protect them from damage. Therefore, as long as the dimensions and weight are correct, there is no cause for concern.

In some silver coins (999 fineness), the last thousandth contains “impurities” such as iron or nickel. A classic example of this is the Krugerrand silver coin (conductivity value: approx. 55–60 MS/m). As a result, the coin’s conductivity value on the GoldScreenSensor often falls into the lower range, even though it is genuine. Additional testing methods will confirm the coin’s authenticity. The same effect can also be observed with other items, such as the “Tokelau 4th Edition Terra | Earth 2021” silver coin.

In fact, the target value for 9999 silver—at approximately 62 MS/m—is slightly higher than that for 999 silver, which is 60.5 MS/m. Of course, in practical measurements, the values may deviate slightly from the target value due to variations in temperature, minting, and packaging. The conductivity values of coins with a fineness of 9999 can therefore fall within the higher range and sometimes also within the lower range. The conductivity value of silver coins containing “only” 999 parts silver out of 1,000 occasionally falls within the lower range or even the adjacent lower range.

1. Compare the dimensions with the manufacturer’s specified dimensions.

2. Check that the weight is correct.

3. Measure the conductivity using eddy current measurement. For the final step, we recommend the GoldScreenSensor for investment metals ranging from 1/4 ounce to approximately 2 ounces (depending on geometry and material).

For more information (including details on various sizes and shapes of precious metals), please visit the Goldtest page.

The battery lasts over 10 hours with active use. Charging takes about 2 hours. If you would like to have your device's battery replaced, please feel free to contact us, and we'll take care of it for you.