Scorodite with Segnitite

📍Clara Mine, Oberwolfach, Ortenaukreis, Freiburg Region, Baden-Württemberg, Germany 🇩🇪
Dimensions: 42 / 22 / 14 mm
Ex. Stefan Röhrig

This specimen from the world-famous Clara Mine in Germany displays a rare and striking association of arsenate minerals. Vivid, flower-like clusters of scorodite crystals line a small vug, their color rich and surfaces sharply defined with strong luster. The base of the cavity is coated with fine-grained segnitite crystals of warm brownish-yellow hue, creating an exceptional visual and mineralogical contrast.

Located deep in the Black Forest of southwestern Germany, the Clara Mine is one of the few active mines still operating in the country. Mining began in the late 19th century, primarily for baryte (BaSO₄) and fluorite (CaF₂). However, the mine is best known among mineralogists for its oxidation zone, which has yielded an extraordinary diversity of secondary minerals — over 400 species documented to date, including numerous rare and type-locality arsenates.

Scorodite from the Clara Mine is celebrated worldwide for its intense coloration and sharp crystal habit, ranking among the best of its kind. Segnitite, by contrast, is much rarer and forms only under specific geochemical conditions involving lead and a lack of sulfates. Their coexistence in the same specimen beautifully illustrates the complex chemistry of the deposit and makes this an exceptional systematic mineralogical piece for any collection.