Rock Identifier
Mookaite Jasper (Silicified Radiolarite (SiO2)) — sedimentary
sedimentary

Mookaite Jasper

Silicified Radiolarite (SiO2)

Hardness: 6.5-7 (Mohs scale), Color: earthy tones of yellow, red, and mustard, Luster: vitreous to dull, Crystal structure: microcrystalline (cryptocrystalline quartz), Cleavage: none, conchoidal fracture.

Hardness
6
Identified More sedimentary
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Physical properties

Hardness: 6.5-7 (Mohs scale), Color: earthy tones of yellow, red, and mustard, Luster: vitreous to dull, Crystal structure: microcrystalline (cryptocrystalline quartz), Cleavage: none, conchoidal fracture.

Formation & geological history

Formed during the Cretaceous period (approx. 145 to 66 million years ago) from the skeletal remains of radiolaria (tiny sea creatures) that were silicified into chert/jasper in a shallow marine environment.

Uses & applications

Extensively used in lapidary work for making cabochons, beads, and polished carvings. Also popular among collectors and used in metaphysical jewelry.

Geological facts

Mookaite is only found in one place in the world: the Kennedy Ranges of Western Australia near Mooka Creek. The name 'Mooka' is an Aboriginal word meaning 'running waters'.

Field identification & locations

Identify by its distinct Australian 'outback' color palette and high polish capabilities. In the field, look for fine-grained, opaque patterns without significant transparency. Commonly found as pebbles in creek beds in the Mooka area.