Dioptase thumbnail on chrysocolla, DRC, 33mm

Description

Mineralogical Profile

This specimen is a superb example of the blocky rhombohedral habit characteristic of high-quality Congolese Dioptase. Unlike specimens that feature a fine druzy coating, this cluster displays distinct, well-defined crystal faces that showcase the mineral’s natural geometric structure.

• Color Profile: Displays the quintessential “electric” emerald-green hue. The saturation is deep and uniform across the specimen, with high transparency on the edges of the primary crystals.

• Luster & Light Return: The crystals possess a high vitreous luster. Due to the larger, flatter faces on this specific piece, the light return is characterized by broad, sharp flashes rather than a scattered shimmer.

• Crystal Habit: Features intergrown rhombohedra that have formed a rugged, three-dimensional topography over a light-colored, silicified matrix.

Technical Specifications

• Chemical Formula: $CuSiO_{2}(OH)_{2}$ (Hydrated Copper Silicate)

• Crystal System: Trigonal / Rhombohedral

• Cleavage: Perfect in three directions (typical of the species, resulting in the sharp internal “shimmers” seen in the depths of the crystals).

• Hardness: 5 on the Mohs scale.

Display Note

This is a robust, “wrap-around” specimen where the mineralization is visible from multiple vantage points. It is best suited for a display where it can be viewed at eye level to appreciate the height and stacking of the crystal formations.