I already posted an article about a DIY gold detector, but this time you can test a much simpler DIY gold detector with an Arduino.
You will need and some other stuff and you can view them in the image below (click on the image to visit the maker of this circuit for more information).
Keep in mind that the transistor must be BC547 and not the 2N.
You must build and the coil, unless you already have one from an older gold detector and you also need to get the code for Arduino.
Solder all items on any board and after you upload the code on Arduino, connect it on board too.
Arduino can be powered up from our PC, so you don't need to disconnect it for you tests. Remember every time you power up Arduino, to press the button (read more in code).