Aluminum has a high electrical conductivity and is a good reflector of electromagnetic radiation. It reflects a wide range of frequencies, including visible light, ultraviolet, and infrared radiation. Due to its reflective properties, aluminum is used in applications such as reflective coatings for insulation and mirrors. It also has the ability to shield against electromagnetic radiation, making it a common material in the construction of Faraday cages, which are used to block external electromagnetic fields. Aluminum's effect on electromagnetic radiation is primarily through reflection and shielding, rather than absorption or transmission.