The rare earth element is used in optical glass and metal halide lamps. Its excellent magnetic properties make it indispensable when it comes to generating particularly strong magnetic fields. It is used as a shielding material in nuclear technology. Laser materials such as yttrium iron garnet, yttrium aluminum garnet and yttrium lithium fluoride, which are required for the production of microwave components and solid-state lasers, are often doped with holmium.