Spoiler alert: there isn't any common ‘most effective metal detector for gold’. (Even though the GPZ 7000 is near for the people of you who can manage a detector that’s precisely the same price tag as a car or truck). The 2 most important coils are connected to an oscillator https://xiglute.com/forums/topic/109411/metal-detector-myths-debunked/view/post_id/736614