People can use it to find iron, mine, gold, some from natural, some are from the past.
Underground Metal Detector help people's life more funs and prosperity. Some Chinese use it to detect underground metal from graves to know more history about their ancestors while people from U.S.A., Australia and Africa use it to detect natural gold. Chinese Underground Metal Detector is cheap but also good in use. And also offer 1 year warranty, it worth your choice!