sedimentary
Kambaba Jasper
Stromatolite (Fossilized Algae within Microcrystalline Quartz)
Hardness: 6.5-7 (Mohs scale); Color: Deep green with black circular or swirling patterns; Luster: Vitreous to dull (polished in photo); Crystal Structure: Trigonal; Specific Gravity: ~2.6.
- Hardness
- 6
- Color
- Deep green with black circular or swirling patterns
- Luster
- Vitreous to dull (polished in photo)
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Physical properties
Hardness: 6.5-7 (Mohs scale); Color: Deep green with black circular or swirling patterns; Luster: Vitreous to dull (polished in photo); Crystal Structure: Trigonal; Specific Gravity: ~2.6.
Formation & geological history
Formed by fossilized prehistoric blue-green algae (cyanobacteria) that created mounds known as stromatolites. Found in the Bongolava region of Madagascar, these date back nearly 3 billion years to the Archean Eon.
Uses & applications
Primarily used for lapidary work, including polished spheres, cabochons for jewelry, decorative home decor, and as a popular stone for crystal healing and mineral collectors.
Geological facts
Despite being called 'Jasper', it is technically an ancient fossil of stromatolites. It is often confused with Nebula Stone or Crocodile Jasper, but its signature 'eyes' (clumps of algae) are unique to its origin.
Field identification & locations
Identify by its unique 'orbicular' dark green/black swirls against a lighter green background. It is mostly found in the West-Central region of Madagascar. Collectors look for high contrast and intact circular patterns.
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