Technical term – ferrous and non-ferrous metals
Ferrous metals are metals or alloys containing iron as the main component. Non-ferrous metals or alloys don’t contain iron in appreciable amounts, e.g. zinc, copper, aluminium, bronze.
Note:
Dutch terminology considers “ferro metals” as metals or alloys with iron, cobalt, nickel or gadolinium as the main component. The spins of the atoms in “ferro metals” can be oriented in the same direction, leading to a temporary or permanent magnetic field. In other words: they can be magnetized. All other metals are considered to be “non-ferro metals" and and cannot be magnetized.
An active detector detects both ferro- and non-ferro metals, a passive detector only ferro metals.
