Mookaite Correctly Known as Windalia Radiolarite
Mookaite which can be an exceptionally colourful stone is a variety of jasper that can only be found in Australia. Used as a decorative material and for its healing properties, it takes on a high polish and when used as a gemstone is shaped as a cabochon.
Made up predominantly of the microscopic remains of minute aquatic organisms called radiolaria, the scientific name for mookaite is windalia radiolarite. The radiolaria measured 0.1 to 0.2 millimetres and produced intricate mineral skeletons. As ancient oceans receded they gradually died out and their skeletal remains slowly transformed into sedimentary rock. Although many different varieties of radiolarite can be found around the world, windalia can only be found in one location in Australia.
Mookaite Named After Mooka Creek
Although named locally after the area where this colourful variety of jasper is found, the name has never been officially registered. According to locals the name is believed to originate from the aboriginal word 'mooka' meaning 'running water'. The mookaite deposit is located on private land in Mooka Creek on Mooka Station, once a sheep farm to the west side of the remote Kennedy Range National Park. This is the only place in the world where mookaite jasper as it's also known can be found.
Although often called 'mookite' the correct pronunciation is 'mooka~ite' because it was named after Mooka Creek. Rocks and minerals that have been named after people or locations are usually given the suffix 'ite'. The mineral sugilite was named after Professor Kenichi Sugi, haematite is named after 'haema' the Greek word for blood, sodalite was named because of its high sodium content and labradorite is named after the coast of Labrador in Canada. My favourite is the mineral Englishite which just like mooka~ite should be pronounced English~ite but rarely is.
Many articles online refer to mookaite by different names all of which strangely, are very similar. Some of these include mookalite, mook, mookerite and mook jasper.
Although frequently referred to as a mineral mookaite is in fact a rock because like most varieties of jasper, it's made up of several different minerals and substances. The colours in the stone are caused primarily by the presence of iron and manganese and along with precious opal, it's one of Australia's best known gemstones.
On Mohs scale of mineral hardness mookaite grades 6 to 7 which means it's a relatively hard stone but one that's also brittle so will break or fracture quite easily. The hardness of rocks and minerals is often confused for toughness but the two characteristics are quite different. Hardness relates a stone's resistance to scratching whereas toughness (correctly known as tenacity) is the way it reacts to stress meaning how easily it breaks, cracks or bends.