sedimentary
Mookaite Jasper
Silicified Radiolarite (SiO2)
Hardness: 6.5-7 (Mohs scale), Color: combinations of red, yellow, mustard, and brownish-maroon, Luster: vitreous to waxy, Crystal structure: trigonal (microcrystalline), Cleavage: none, Specific gravity: approx. 2.65
- Hardness
- 6
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Physical properties
Hardness: 6.5-7 (Mohs scale), Color: combinations of red, yellow, mustard, and brownish-maroon, Luster: vitreous to waxy, Crystal structure: trigonal (microcrystalline), Cleavage: none, Specific gravity: approx. 2.65
Formation & geological history
Formed from the fossilized remains of radiolaria (microscopic protozoa with silica skeletons) that settled on the sea floor and were compressed and silicified during the Cretaceous period (approx. 66-145 million years ago).
Uses & applications
Widely used for lapidary work, cabochons, beads, ornamental carvings, and a popular specimen for gem and mineral collectors.
Geological facts
Mookaite is found specifically in the Kennedy Ranges of Western Australia near Mooka Creek. The name 'Mooka' is an Aboriginal word meaning 'running waters'. It is unique for its earthy 'warm' color palette.
Field identification & locations
Identify by its distinct yellow-and-red banding, opaque appearance, and conchoidal fracture. In the field, look for dense, chert-like nodules in weathered white pipe clay (kaolin).
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