Cluster XL Malachit with Botrioidal Crisocola Brusta | Model 1

Size 16 x 11 x 10 cm

Country of origin: Congo

This imposing piece, naturally formed, represents a spectacular meeting between two secondary minerals in the oxidation area of ​​copper deposits: Malachite and chrysocolla. The dominant botrioid structure - characterized by globular aggregates reminiscent of a mass of solidified drops - is a rare expression of slow formation, under specific hydromineral conditions, often in cavities where copper -rich solutions have gradually precipitated on the walls of geological voids.

Malachite, a copper carbonate (cu₂co₃ (OH) ₂), is noted for its concentric green shades, sometimes with fine strips or with velvety texture in the case of crystallization in the form of fibrous aggregates. In this piece, it serves as a basic matrix, forming smooth, compact surfaces, but also slightly undone reliefs.

chrysocolla, a copper hydrated silicate with amorphous structure (Cu₂-Xalx (H₂-XSI₂O₅) (OH) · · NH₂O), is deposited in intersections or forms coating in shades of blue-green, completing with finesse the botrioid structure of the malachite. The presence of crisocol in this context indicates a chemical evolution of the geological environment, with pH variations and changes in the composition of mineral solutions.

This mineralogical association is typical of regions rich in oxidized copper deposits, such as those in Congo (Katanga), Peru, Arizona or Israel, but shades, morphology and aggregation varies depending on the geographical origin. The present specimen is noted by the unusual size, the well -defined botrioid texture and the intense chromatic contrast - highly sought after features.