Rocks below have been shown in Studies reguarding protection from EMF exposure.
More information can be found here ----> https://hibiscusmooncrystalacademy.com/crystals-lower-emf-risks/
Please Note; While Hematite and Pyrite are commonly recommended for this purpose, please note that it is not a good idea to use them next to some devices as they can cause the device to malfunction. Use with care and caution!!
Also; WARNING: be certain not to have any strongly magnetic stones near your laptop or other devices = can cause LAPTOP DEATH due to hard-drive being erased.