system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If Iron, Nickel, and Cobalt are the only magnetic elements, then how/why do rare earth metals make stronger magnets?
gpt
The rare earth metals are magnetic, but only at lower temperatures. By combining them with iron, nickel, and cobalt in alloys, you can raise the temperature at which their magnetism would normally disappear. The stronger magnetic field comes partly from the high number of unpaired electrons they have.