mineral
Metallic sulfide-bearing rock, possibly galena-rich ore
Likely galena (PbS) with iron sulfides and gangue; exact identification requires testing
AI-generated identification · may be incorrectDark gray to black, coarse and irregular, with bright metallic luster and scattered reflective grains. Galena has Mohs hardness 2.5–2.75, cubic crystals and perfect cubic cleavage; the specimen’s apparent brown weathering may indicate oxidation and mixed sulfides.
Identified More mineral →
Explore Metallic sulfide-bearing rock, possibly galena-rich ore in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Dark gray to black, coarse and irregular, with bright metallic luster and scattered reflective grains. Galena has Mohs hardness 2.5–2.75, cubic crystals and perfect cubic cleavage; the specimen’s apparent brown weathering may indicate oxidation and mixed sulfides.
Formation & geological history
Likely formed in hydrothermal veins or replacement deposits when hot, mineral-rich fluids precipitated sulfides in fractures, commonly during the Paleozoic to Mesozoic or younger. Weathering can produce brown iron-oxide coatings.
Uses & applications
Galena is an important historical lead ore and silver source; specimens are collected for their metallic appearance, but lead-bearing material should not be used in jewelry or handled without washing hands.
Geological facts
A heavy specimen with cubic cleavage and a gray streak would strongly support galena; magnetism would suggest associated magnetite rather than pure galena. Do not grind, ingest, or create dust because lead sulfides are toxic.
Field identification & locations
Common in lead-zinc districts worldwide, including Missouri, Idaho, Colorado, Peru, Australia and England. Confirm with specific gravity, streak, cleavage and ideally X-ray fluorescence; visual identification alone is uncertain.
