3.6" Galena With Sphalerite - Pine Point Mine, Canada
This specimen contains galenaand sphalerite crystals, and was collected from the Pine Point Mine in Canada. The sphalerite formed as a druze, encrusting botryoidal structures from the matrix. Galena can be found in various crystal structures around the specimen. The beautiiful layering of the crystals on matrix can be seen when viewing sections of the specimen where removal/extraction took place. This is a truly fascinating specimen.
Sphalerite is a part of the sulfides group and typically exhibits a grey/black appearance due to high concentrations of impurities. When sphalerite is in it's purest state, the chemical composition is ZnS, and can display a gemmy transparent light tan/yellow color. This is one of the few minerals that can form crystals ranging anywhere between gemmy and transparent to opaque and metallic-like. Opaque or cloudy sphalerite tends to be most abundant, due to the ease of iron replacing zinc in the process of formation.
Galena is a lead based mineral that is in fact the primary ore of lead, and has been used for its lead content for thousands of years. Galena typically displays a gray metallic luster and forms cubes or octahedral crystals. The chemical composition of galena is PbS.