Metal detectors are highly effective at finding most types of metal buried underground. They work best on ferrous and non-ferrous metals, like coins, jewelry, and relics. Their success, however, depends heavily on the item’s metal, size, and depth. Many people use them for hobby treasure hunting or professional security screening. We found that effectiveness isn’t…

Metal detecting is the practice of using a portable electronic device to find metallic objects hidden underground or underwater. Its history began with the invention of the metal detector in the 19th century, but the hobby we know today took off much later. We found that early devices were large, complicated, and designed for industrial…