What is Rozenite?
Rozenite is a soft hydrated iron sulfate, usually pale and powdery, formed in acidic weathering environments and valued as a delicate secondary mineral.
Mineralogy and crystal structure
Reference formula: FeSO4·7H2O. Rozenite is monoclinic and highly hydration-sensitive. The selected COD model represents the heptahydrate structure, but humidity and dehydration can change the specimen over time. Rozenite is classified with sulfates and has a monoclinic crystal system. Typical hardness is 2–2.5 on the Mohs scale and specific gravity is approximately 1.9–2.1.
Colour, lustre and habit
Typical colours include white, pale green, yellow, blue-green. The usual crusty, fibrous, massive habit and vitreous, pearly lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Rozenite forms in or is associated with oxidation of iron sulfides in mine dumps, coal measures and acidic sulfate environments. Important documented localities include the Czech Republic, Germany, Slovakia, Spain, the United States and other mine-weathering localities.
A fragile sulfate born from mine weathering
Rozenite is a mineral of environment and time: acidic fluids created it, while ordinary humidity can transform it. Its value depends on freshness, careful storage and documented occurrence.
Collecting and care
Keep sealed, cool and completely dry. Avoid water, humidity, heat and direct handling; store with a stable label and matrix.
