Hi guys , you've all probley heard this question before or pondered it you self but I was wondering about detecting inside mine tunnels would this be a productive exercise to find possibly missed gold ? or o over the mullock heaps around them , Ive plenty of reef mines in the area and am confused as where to start looking , a dozer has just cleaned the track and I also thought I could just walk the track as new round has been opened up any input would be greatly appreciated , cheers .