sedimentary

Mookaite Jasper

Silicified Porcellanite (SiO2 with impurities)

Hardness: 6.5-7 (Mohs scale); Color: Earthy tones including maroon, mustard yellow, cream, and tan; Luster: Vitreous to greasy (highly polished); Crystal system: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific gravity: 2.63-2.65.

Hardness: 6
Luster: Vitreous to greasy (highly polished)

Identified March 9, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from the skeletal remains of radiolaria (microscopic marine organisms) deposited in shallow sea beds during the Cretaceous period (approx. 145 to 66 million years ago). These remains were later silicified by silica-rich groundwater.

Uses & applications

Predominantly used as a semi-precious gemstone in jewelry (pendants, beads, cabochons) and as a popular specimen for collectors and metaphysical practitioners.

Geological facts

Mookaite is found exclusively in the Mooka Creek area of Western Australia. The name 'Mooka' is an Aboriginal word meaning 'running waters.' It is unique because it combines features of both jasper and chert.

Field identification & locations

Identify by its distinctive opaque pastel 'desert' color palette and high levels of polish. In the field, look for brittle, glass-like outcroppings in specific Australian drainage basins. Collectors should look for vibrant banding and lack of cracks.

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