Frequently Asked Questions | Goldanalytix
Here you find answers to the most frequently asked questions on all topics related to precious metal testing. The questions and answers are neatly arranged according to key topics - so you can find what you are looking for very quickly.
In some silver coins (fineness 999) there are "impurities" in the last thousandth in the sense of e.g. iron or nickel, which can be traced back to unclean production methods in the past. The classic coin for this is the Krugerrand silver (conductivity: approx. 55 - 60 MS/m). This means that the coin often slips into the copper range or below on the GoldScreenSensor, although it is real.
Additional measuring methods will confirm the authenticity of the coin.
The same effect can also be seen with other objects such as the silver coin "Tokelau 4th Edition Terra | Earth 2021".