▁rot ating ▁( hand - c rank - power ed ) ▁motion ▁ ▁industrial ▁uses ▁such ▁as ▁maintain ing ▁product ▁pur ity , ▁equipment ▁protection , ▁and ▁quality ▁control ▁ ▁capture ▁of ▁fine ▁met all ic ▁particles ▁in ▁lub ric ating ▁o ils ▁( c rank cases ▁of ▁internal ▁comb ust ion ▁engines , ▁also ▁g ear box es ▁and ▁differential s ), ▁so ▁as ▁to ▁keep ▁said ▁particles ▁out ▁of ▁circul ation , ▁thereby ▁rendering ▁them ▁unable ▁to ▁cause ▁ab ras ive ▁wear ▁of ▁moving ▁machine ▁parts ▁ ▁Other ▁applications ▁ ▁Other ▁applications ▁of ▁rare - ear th ▁magnet s ▁include : ▁Linear ▁mot ors ▁( used ▁in ▁mag lev ▁trains , ▁etc .) ▁Stop ▁motion ▁animation : ▁as ▁tie - down s ▁when ▁the ▁use ▁of ▁traditional ▁sc rew ▁and ▁nut ▁tie - down s ▁is ▁imp ract ical . ▁Diam agnet ic ▁lev itation ▁experiment ation , ▁the ▁study ▁of ▁magnetic ▁field ▁dynamics ▁and ▁super con duct or ▁lev itation . ▁Elect rod ynamic ▁bear ings ▁La unch ed ▁roll er ▁co aster ▁technology ▁found ▁on ▁roll er ▁co aster ▁and ▁other ▁thr ill ▁r ides . ▁LED ▁Th row ies , ▁small ▁LED s ▁attached ▁to ▁a ▁button ▁cell ▁battery ▁and ▁a ▁small ▁rare ▁earth ▁magnet , ▁used ▁as ▁a ▁form ▁of ▁non - dest ruct ive ▁gra ff iti ▁and ▁temporary ▁public ▁art . ▁Ne od ym ium ▁magnet ▁to ys ▁Electric ▁guitar ▁pick ups ▁M ini ature ▁figures , ▁for ▁which ▁rare - ear th ▁magnet s