Jarosite

Unknown Owner

Richly crystallized micro jarosite across the front of matrix. In great condition, a fine cabinet sized example for the species.Jarosite is a potassium iron sulfate mineral that typically forms in the oxidized zones of sulfide ore deposits. It develops when iron rich sulfide minerals such as pyrite break down through weathering in the presence of water and sulfuric acid. Jarosite commonly appears as yellow to brown earthy masses or small crystals and is often associated with minerals such as goethite, limonite, and gypsum. It is an important indicator mineral for acidic conditions in mining environments and has also been identified on the surface of Mars by spacecraft exploration.