Galena and sphalerite: the classic ore pair

Galena is lead sulfide, notably heavy for its size due to the lead content, with perfect cubic cleavage that often leaves broken pieces looking like small silver gray cubes or stair stepped fragments. Its streak is gray to black. Sphalerite, zinc sulfide, is commonly found alongside galena in the same ore deposits and has a distinctive resinous, almost waxy luster along with a much lighter streak, usually pale yellow to light brown. Both were, and in many places still are, economically important ores, and finding them together in old mine tailings (with proper permission) is common since they so often form in the same hydrothermal deposits.