Mookaite Jasper
Radiolarian Jasper / Silicified Porcelanite · Semi-Precious Gemstone / Ornamental Mineral
Crystal System
Trigonal (microcrystalline); usually occurs as massive, opaque blocks without visible crystal faces.
Mineral Group
Silicates (Tectosilicate); Oxide mineral class (Quartz group)
Chemical Formula
SiO2 with inclusions of Goethite (FeO(OH)) and Hematite (Fe2O3)
Formation Process
Sedimentary; formed by the silicification of radiolarian siltstone/opalite as silica-rich groundwater replaced organic remains.
About This Crystal
This specimen is a polished tumble showing a characteristic bi-color pattern of deep burgundy-purple and mustard yellow. It is fully opaque with a silky to vitreous luster and a smooth, waxy surface texture.
Physical Characteristics
Color: Maroon, yellow, and cream; Streak: White; Cleavage: None; Fracture: Conchoidal to splintery; Specific Gravity: 2.6 – 2.7; Fluorescence: Generally inert.
Optical Properties
Opaque; Refractive Index: approximately 1.54 - 1.55; Lacks pleochroism and birefringence due to microcrystalline aggregate structure.
Hardness & Durability
Origin Region
Mooka Creek, Kennedy Ranges, Western Australia; formed in a shallow marine environment from decaying radiolaria.
Hardness & Durability
Mohs Hardness: 6.5 – 7.0; High toughness; Excellent durability for jewelry and everyday handling.
Care & Maintenance
Clean with warm soapy water and a soft cloth; avoids harsh chemicals. Store separately from harder gemstones like diamonds to prevent scratching.
Rarity & Value
Locally abundant but geographically limited to Western Australia; affordable price range; rarely treated or dyed.
Special Characteristics
Features a unique 'porcelanous' texture and earthy, opaque color banding caused by varying iron oxide concentrations.
Lore & History
Known as the 'Mother Earth' stone in Australian folklore; traditionally associated with vitality, grounding, and connection to ancestral spirits.