Dalekanium was bulletproof and immune to most lasers and bombs, making a Dalek hard to defeat. It could attract gamma radiation. Dalekanium panels were attached to the Empire State Building in 1930 to attract gamma radiation, which would introduce Dalek DNA into humans that the Cult of Skaro had captured. (TV: Evolution of the Daleks) Metalert was a reinforced type of Dalekanium. The casing was infused with Flidor gold and sap from the extinct Arkellis flower. The rarity of these substances meant that only Dalek Sec used this substance. (PROSE: Birth of a Legend)