Metal Detector HD Prank

Technically speaking only metals that contain ferrimagnetic elements such as iron, nickel and cobalt will register variations onscreen.

When a ferrimagnetic metal object obscures the natural magnetic field and the result is shown realtime on the graph. Different shapes and sizes of metal contain ferrimagnetic elements will all register in a different ways; long thin items like screwdrivers seem to have to greatest effect so have fun experimenting!