Ferrite magnets are often referred to as Ceramic magnets. Ferrite magnets have two poles, Normally north on the one face and south on the other face (magnetized through the thickness)
Ferrite Anisotropic magnets are black in color and are supplied uncoated. These magnets do not corrode and can be used outdoors or in wet conditions without any problems. They are relatively inexpensive.
These magnets can handle up to 250degrees Celsius and they have high coercivity, meaning they are difficult to demagnetize.