sedimentary

Mookaite Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

Hardness: 6.5-7 (Mohs scale); Color: Red, yellow, mustard, cream, purple, and brown; Luster: Vitreous to dull; Crystal structure: Trigonal (microcrystalline); Cleavage: None/Conchoidal fracture; Specific gravity: 2.6-2.7

Hardness: 6
Color: Red, yellow, mustard, cream, purple, and brown
Luster: Vitreous to dull

Identified May 10, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed as a silicified porcellanite or radiolarite. It comes from the Windalia Radiolarite formation in Western Australia, created from the tiny skeletal remains of radiolarians that settled on the sea floor during the Cretaceous period approximately 100-145 million years ago.

Uses & applications

Widely used in jewelry for cabochons and beads, ornamental carvings, lapidary arts, and as a popular collector's specimen due to its unique vibrant patterns.

Geological facts

Mookaite is found only in the Kennedy Ranges near Gascoyne Junction in Western Australia. The name 'Mooka' comes from the Aboriginal word for 'running waters' in reference to Mooka Creek where it is found.

Field identification & locations

Identify by its distinctive earthy color palette (mustard yellow combined with brick red), its very smooth conchoidal (shell-like) fracture edges, and high hardness. It is typically found in crumbly decomposed rock beds in semi-arid regions.

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