Lead sulfide, also known as GALENA, is a naturally occurring mineral composed of lead and sulfur. It is the primary ore of lead and has been used since ancient times for a variety of purposes, including jewelry and medicine. GALENA is a grayish-black metallic mineral with a metallic luster and a high specific gravity. It is often found in hydrothermal veins and sedimentary rocks. GALENA is an important source of lead and is used in many industrial applications.