Uraninite is a mineral primarily composed of uranium dioxide (UO2) and is the most significant ore of uranium. It typically appears as black or brownish-black in color and has a metallic luster. Uraninite is often found in igneous and metamorphic rocks and can form in various geological environments. This mineral is crucial for the nuclear energy industry, as it is a primary source of uranium used in nuclear reactors. When mined, uraninite undergoes processing to extract uranium, which is then utilized for electricity generation and other applications in the field of nuclear technology.