containing heavy rare earth elements a solid solution containing heavy rare earth elements a compound containing heavy rare earth elements and a rare earth metal nitrate hydrate with an organic solvent to prepare the heavy rare earth source slurry the heavy rare earth elements include but are not limited to dy tb and ho the metal powder of the heavy rare earth elements at least contains a heavy rare earth element and the average particle size of the powder is 1 u03bcm to 100 u03bcm the compound containing the heavy rare earth elements includes at least one of a rare earth metal hydride a rare earth metal fluoride and a rare earth metal oxide the alloy containing the heavy rare earth elements is represented by r a m b or r x t y m z wherein r is selected from at least one of the heavy rare earth elements m is selected from at least one element of al si c p ti v cr mn ni cu zn ga ge zr nb mo ag in sn sb hf ta w pb and bi and t is selected from at least one of fe and co wherein a and b x y and.