Surveys with Metal Detector are usually executed to detect buried metal objects.

It is an instrument suitable for archaeological surveys, especially for the research of small metal finds.

The metal detector transmits radio waves by a portable antenna and, at the same time, records back signals. If no metal is presents, the radio wave gets dispersed; but if it hits a metal object, it is reflected back to the surface and recorded.

The depth of investigation depends on various factors: the quality of the device used, depth, shape and size of the searched objects.