Mookaite Jasper is a silicified radiolarian sedimentary rock (chalcedony) from Mooka Creek, Western Australia, composed mainly of SiO₂ with iron oxide colorants. It has a white streak, hardness 6.5–7 Mohs, SG ~2.6, no cleavage, and a conchoidal fracture. Its earthy reds, yellows, creams, and purples make it highly prized in lapidary and decorative uses, and it is unique to Australia.

Found only in Mooka Creek, Western Australia (hence the name) formed during the Cretaceous period (~145–66 million years ago). Originates from radiolarian chert, a sedimentary rock composed of silica-rich microscopic marine organisms (radiolaria) over time, these siliceous sediments were silicified and colored by iron oxide minerals.