Great question! MAGNA-TILES® sets are crafted with high-quality ceramic magnets, while Magna-Qubix® are made with rare earth neodymium magnets. Our ceramic (aka, ferrite) magnets are made to resist corrosion and demagnetization for years of lasting strength. It’s worth noting that exposure to extremely high temperatures (480 degrees Fahrenheit or above) will permanently reduce the strength of ceramic magnets. It’s highly unlikely your MAGNA-TILES pieces will be exposed to that much heat, but just an FYI.