I assume Magnets are added in an upcoming update...along with neodymium...so won't show yet. Unless magnets are already in and i missed something in the changelog.
(apparently, breathing in neodymium dust can cause lung embolisms...though i'm not suggesting an in-game debuff)
Many of the dusts in Gregtech are detrimental to the lungs. Neodymium is most commonly found in Monazite along with the lighter Lanthanides and Thorium, the heavier Lanthanides are found in Xenotime. Monazite is found often in placer deposits and I think Ecoglite or Basalt. I also don't know what mineral in PFAA would give Neodymium as Monazite is not in PFAA.