“Mookaite” is a locally-coined name for a lower Cretaceous siltstone found in Western Australia. The siltstone consists largely of microscopic organisms known as Radiolarians, which possess an unusual skeletal structure made up of opaline silica. Mookaite is best defined as a silicified porcelanite known as Windalia Radiolarite, whose silification is opaline to chalcedonic. The main locality for Mookaite is near Mooka Station, a former sheep station in the southeastern end of Western Australia’s Kennedy Range. Metaphysically, it is used for conception of ideas and new beginnings.