3.6" Blue Veszelyite Crystals on Botryoidal Hemimorphite - Congo

Veszelyite is a rare secondary copper and zinc mineral found in the oxidation zones of base metal deposits. Veszelyite crystals are typically emerald green, blue or a mixture of the two. They can be found as small, lustrous clusters peppered across other minerals or as crusts, but in rare cases they can also be found as dense crystal aggregations.

Veszelyite specimens from a recent (2019/2020) find in the Bouenza Department of the Republic of the Congo (Brazzaville) are a perfect example of this rare instance of dense aggregations of veszelyite. Within the hemimorphite zone of the Palabanda Quarry, irregularly dispersed formations of this rare mineral were unearthed. They occurred in small brecciated/weathered cavities where most of the veszelyite formed as crusts, while some spots revealed well formed crystals over hemimorphite. The area that contained these crystals was mined over five months, the final two of which appeared to indicate that the pocket was completely exhausted.

About Hemimorphite From The Congo

Bemimorphite from the Democratic Republic of the Congo is prized for its vivid sky-blue to turquoise coloration and delicate crystal forms. These specimens typically occur as botryoidal crusts, sparkling druzy surfaces, or finely crystallized aggregates lining fractures and cavities in the host rock. The color is caused by trace copper within hemimorphite’s zinc silicate composition, giving Congolese material a brighter, more saturated blue than most other localities.

Hemimorphite is a hydrous zinc silicate that forms in the oxidation zones of zinc ore deposits, often replacing earlier zinc minerals. It is named for its “half-shaped” crystals, which display different terminations at each end—a distinctive but often subtle feature in well-crystallized examples. In the copper-rich deposits of the DRC, hemimorphite is commonly found associated with malachite, smithsonite, dioptase, and limonite. Its glassy to silky luster, intricate surface textures, and geological significance make blue hemimorphite from the Congo a standout display mineral for collectors.