Galena is the natural mineral form of Lead Sulfide. It is the most important Lead ore mineral and is one of the most abundant and widely distributed sulfide minerals. It is often associated with Sphalerite, Calcite and Fluorite. Galena deposits often contain significant amounts of Silver, Zinc, Cadmium, Antimony Arsenic and Bismuth. It is used as a semiconductor in early wireless communication systems. It is usually dark grey to black in color with a shiny iridescence.