sedimentary

Jasper (likely Kambaba or Crocodile Jasper variety)

Silicon Dioxide (SiO2) with inclusions

Hardness: 6.5–7 (Mohs). Color: Dark green with black or grey concentric circles or mottling. Luster: Vitreous to dull. Structure: Microcrystalline (cryptocrystalline) quartz. Cleavage: None (conchoidal fracture).

Hardness: 6
Color: Dark green with black or grey concentric circles or mottling
Luster: Vitreous to dull

Identified March 25, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the fossilization of prehistoric algae (Cyanobacteria) colonies, specifically stromatolites, often dating back 3 billion years. Predominantly found in the rift valley of South Africa and Madagascar.

Uses & applications

Used primarily in lapidary arts as tumbled stones, beads for jewelry, ornamental carvings, and by collectors for its unique prehistoric origins.

Geological facts

Despite being called 'Jasper', Kambaba Jasper is actually a stromatolite fossil. It is one of the oldest known fossils on Earth and contains some of our earliest evidence of life (primordial algae).

Field identification & locations

Identify by its characteristic 'orbicular' or 'eye-like' patterns and dark forest green base. It is cold to the touch and cannot be scratched by a steel blade. Found typically in volcanic or sedimentary layers in Madagascar.

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