Pyrite, also known as fool's gold, is a common sulfide mineral. It has a pale brass-yellow reflective color that can tarnish darker and iridescent over time. Pyrite has a cubic crystal habit, but it can also be octahedral and pyritohedral. It is one of the most abundant minerals on Earth and can be found in various forms such as inter-grown, massive, radiated, granular, globular, and stalactitic. Pyrite is denser than water and will sink to the bottom, but it is lighter and easier to move under gentle water movement.