Origin: Haneti-Itiso Area, Central Tanzania

Description: Chrysoprase from Tanzania is a nickel-colored variety of chalcedony known for its vivid green tones, ranging from pale apple green to deeper, more saturated hues. Unlike emerald or chrome-rich minerals, its color comes from trace nickel dispersed throughout the silica structure, giving it a softer, more even appearance. In rough form, it often shows a slightly waxy surface and can vary from semi-translucent to more opaque depending on the concentration of silica and inclusions.

This material forms through the weathering of ultramafic rocks—iron- and magnesium-rich rocks that also contain nickel. As these rocks break down near the Earth’s surface, silica-rich fluids move through the fractured material and redeposit microcrystalline quartz, incorporating nickel into the structure. The result is chrysoprase forming in veins, nodules, or pockets within lateritic soils and silcrete zones. Tanzania’s deposits, particularly in the Haneti region, are known for producing high-quality rough with consistent color suitable for lapidary work.

Chrysoprase is often associated with renewal, optimism, and steady personal growth. Its bright green color gives it an uplifting quality that many people find energizing without being overwhelming. It’s commonly chosen by those looking for a stone that feels fresh, balanced, and quietly motivating.

Chemical Composition: SiO₂ (silicon dioxide) with nickel impurities (Ni²⁺)

Grade: Lapidary
Appearance: Translucent
Cracks: Many
Inclusions: Minimal

Approximate Size of 1 pc: 11cm x 4cm x 1.5cm
Approximate Weight of 1 pc: 75g

Rough is rough. We do our best to grade and describe pieces in the lot, but ultimately, they all differ.