This stunning multi colored stone is found in the Kennedy Ranges near Gascoyne Junction which is about 100 miles inland from the coastal town of Carnarvon in Western Australia, which in turn is about 600 miles north of the capital, Perth.
The name "mookaite" is derived from the locality where the rock is dug, namely Mooka Creek. According to locals, the Aboriginal word "mooka" means "running waters", no doubt in reference to the many fresh water springs that feed Mooka Creek.
Mookaite is sometimes incorrectly called mookite, mookalite, mookerite, mook, mook jasper, moukaite, moakite, moukalite & mouakite.
Mookaite can be described as chert, opalite, chalcedony or combinations of the three. The degree of silica in the material determines its description. This creates difficulties when mining the deposit as the more opaline material can be extremely brittle. It is almost useless for cutting as the lightest tap will cause it to fracture.
The best material is the chalcedonic variety.
After mining many hundreds of tons of mookaite, the miner come to the conclusion that silica rich & mineralized solutions have seeped through the radiolarite pavement beneath the floor of the usually dry creek bed. These solutions have concentrated in various horizons and formed as nodules & sheets of multi colored chalcedony.
Subsequently, the radiolarite with less silica has decomposed into beds of soft white clay which now surround the stunning nodules. Unfortunately there is a fair degree of underground water lying & running through these clay beds which make it extremely messy & difficult for them.