If it can‘t be blocked, what material would weaken the magnetic field the most. Lead, wood, plastic, etc. Thanks for any help.
Yes. A nonmetallic cover of the appropriate thickness for the strength of any particular magnet can be used to prevent the magnetic pull on othe magnets or metallic objects.
mumetal is best, soft iron is next best. But they don't totally block it, they just deflect it. You would need to put the object to be shielded inside a mumetal box, or put the magnet into the box, one or the other. In other words, if you put a piece of mumetal on the end of one pole of a magnet, the magnetic field would just detour around it. The lines still have to reach the other pole, which is unshielded.
