The oldest artificial pigment known to man, which was invented by ancient Egyptians, can be applied to save and generate energy, according to a study conducted by Berkeley Labs The study shows that since the dye, dubbed “Egyptian Blue,” can emit as much as 100% of the light it absorbs, it can potentially be painted on rooftops to keep buildings cool and reduce reliance on ACs, as well as generate electricity through concentrating the light photons it emits. The ancient Egyptians had originally intended to use it as color for their depictions of pharaohs and gods in tombs, but researchers are increasingly finding modern applications for the pigment, including in anti-forgery and medical scanning techniques.