Galena occurs as a heavy, silvery-grey mineral with a distinctive metallic luster and a tendency to form perfect cubic crystals, properties that made it easy for ancient and medieval miners to recognize even without any chemical test. Roasting galena ore in air and then smelting the resulting oxide with charcoal reduces it to metallic lead, a metallurgical sequence practiced since deep antiquity across the Near East, the Aegean and beyond, making lead one of the earliest metals worked at any real scale. Many galena deposits also carry a significant proportion of silver locked within the lead sulfide structure, and separating that silver from the bulk lead, a process called cupellation in which molten lead is oxidized away under a blast of air while silver, resistant to that oxidation, remains behind as a bead of pure metal, was one of the most economically important metallurgical operations of the ancient and medieval world, the source of much of the silver coinage of antiquity.
Galena's association with lead made it firmly Saturnian in alchemical terms, sharing lead's reputation as the heaviest, densest, and most sluggish of the seven classical metals, qualities Saturn was held to govern generally. Alchemists interested in transmuting lead toward gold, moving a base metal up through the planetary hierarchy toward the Sun's perfection, naturally took a close interest in galena as lead's raw mineral source.