sedimentary

Kambaba Jasper (Crocodile Jasper)

Stromatolite (Fossilized Algae within Microcrystalline Quartz), SiO2

Hardness: 6.5-7 (Mohs scale); Color: Dark forest green with black orbicular swirls/spots; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.9

Hardness: 6
Color: Dark forest green with black orbicular swirls/spots
Luster: Vitreous to waxy

Identified March 14, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from fossilized blue-green algae (cyanobacteria) dating back over 3 billion years (Archean Eon). These colonies created layered sedimentary structures called stromatolites, which were later replaced by silica.

Uses & applications

Primarily used as an ornamental stone for jewelry (cabochons), interior decor, meditation aids, and geological specimen collecting.

Geological facts

Despite the name 'Jasper', it is technically a fossilized microorganism formation. It is one of the oldest known fossils on Earth, representing some of the earliest oxygen-producing life forms.

Field identification & locations

Identify by its unique 'crocodile skin' pattern of dark green and black swirls. Best found in the Bongolava region of Madagascar. Collectors look for high-contrast 'eyes' or circular patterns and a smooth polish without surface pits.

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