Dioptase

Unknown Owner

Superb thumbnail specimen with prismatic lustrous slightly translucent green crystals of dioptase in a cluster with little attached matrix. In excellent condition.Reneville, located in the Kindamba District of the Republic of the Congo, is a legendary locality famous for producing some of the worlds finest specimens of the copper silicate dioptase. Geologically, the deposit is a secondary oxidation zone of a copper-lead-zinc ore body hosted within Neoproterozoic carbonates and sandstones of the Schisto-Calcaire Group. The dioptase formed in vugs and fractures where silica-rich meteoric waters interacted with primary copper minerals, resulting in the growth of intensely emerald-green, rhombohedral crystals that are often associated with plancheite or cerussite. Historically, the locality was discovered during the early 20th century under French colonial administration, with systematic mining reaching its peak between the 1950s and the 1970s. While industrial-scale mining has long since ceased, the site has seen a significant resurgence in recent years due to dedicated artisanal mining. These modern efforts by local miners have successfully uncovered new pockets of high-quality material, ensuring that fresh, world-class specimens from this classic locality continue to reach the global market.