Scorodite is a hydrated iron arsenate (FeAsO4·2H2O) best known for its enchanting blue to blue‑green hues and glassy luster. It forms in the oxidation zone of arsenic-bearing deposits (especially arsenopyrite), typically as sharp orthorhombic prisms and dipyramids, drusy coatings, rosettes, or ball-like aggregates, often perched on limonite/goethite gossan. While microcrystals are common, sizable, sharp, translucent crystals are decidedly rare and highly prized. The best pieces combine saturated color, gemmy clarity, and crisp form with striking contrast on dark iron oxides or pale quartz.
Collectors value scorodite for several reasons:
As with most arsenates, scorodite is brittle and sensitive to harsh cleaning. It is safe to display and handle with normal care, but mindful, informed stewardship keeps both the specimen and the collector safe.
Scorodite’s popularity has surged with modern finds—especially in China—bringing exceptional, gemmy blues to market that were scarcely seen a generation ago. Classic older sources like Ojuela and Tsumeb produced elegant, smaller crystals and rosettes long treasured by connoisseurs. Today, scorodite straddles two worlds: accessible as attractive micros, yet capable of commanding strong prices when crystals are larger, transparent, and on aesthetic matrix. Because outstanding examples remain uncommon, top pieces are quickly absorbed into major collections.
Below are renowned localities that consistently produced notable scorodite specimens. Each locality has a distinctive style that advanced collectors recognize immediately.
The Ojuela Mine (Mapimí, Durango) is a classic scorodite source. Its crystals typically form as blue-green rosettes, sprays, and drusy coatings on ocherous gossan, with associations including adamite, mimetite, aurichalcite, and legrandite. While most crystals are small (millimeters), they can be surprisingly sharp and vibrant, with strong contrast on dark iron oxides that display beautifully. Matrix specimens showing multiple rosettes in balanced compositions are particularly prized.
The legendary Tsumeb deposit occasionally produced scorodite, albeit infrequently compared to its famed arsenates. Tsumeb scorodite tends toward sharp, dark blue to blue‑green crystals and druses on limonite or carbonate matrix, sometimes with distinctive associations. Specimens are rarities from a storied mine, prized for provenance and for their crisp crystal form reflective of Tsumeb’s geochemical complexity.
With patient selection and careful stewardship, scorodite rewards collectors with some of the most alluring blues in the arsenate world—small jewels of the oxidation zone that shine brightly in any cabinet.
Amethyst
Quartz
Fluorite
Tourmaline
Malachite
Azurite
Rhodochrosite