sedimentary

Mookaite (Mookaite Jasper)

Silicified Radiolarite (SiO2 with iron oxides)

Hardness: 6.5-7 (Mohs scale); Color: Variegated shades of red, mustard yellow, burgundy, and cream; Luster: Vitreous to waxy; Crystal structure: Microcrystalline (trigonal); Cleavage: None/Conchoidal fracture; Specific gravity: 2.6-2.7

Hardness: 6
Luster: Vitreous to waxy

Identified March 25, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from the fossilized remains of radiolaria (microscopic marine organisms) deposited as silt in shallow sea beds. Over millions of years, chemical-rich groundwater silicified the sediment. Geological age is Lower Cretaceous (approx. 115 million years ago).

Uses & applications

Primarily used as a lapidary material for jewelry (cabochons, beads), decorative carvings, and as a popular semi-precious stone for crystal collectors and metaphysical practitioners.

Geological facts

Mookaite is found only in one place in the world: the Kennedy Ranges of Western Australia, near Mooka Station. The name 'Mooka' is derived from the Aboriginal word for 'running waters', referring to the springs in the area.

Field identification & locations

Identify by its unique earthy color palette (specifically the mustard-to-burgundy swirls) and its high degree of silicification, making it very hard and capable of a mirror-like polish. It is commonly found in creek beds and outcrops near Gascoyne Junction.

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