Galena is Lead Sulfide PbS, and it is one of the primary ore minerals of Lead Pb. Galena, as lead ore, was given its name by the Roman naturalist and author, Pliny the Elder. Galena is a common mineral and often found along with other sulfides in mines here in Arizona.
This mineral has an isometric crystal system, which means that Galena crystals are variously sized cubes. The cubic crystals like these are bright and shiny when fresh, but become duller and tarnished over time.
Galena is soft, with a Mohs' hardness of 2.5. It is also very brittle and has a crumbling, grayish black streak when scraped on an unglazed ceramic plate. Galena is quite heavy, with a specific gravity of 7.4 to 7.6, which is not surprising since Lead is a major component. Because of its Lead content, Galena is poisonous, and so you should wash your hands after handling specimens of this gray mineral.