Mookaite Properties, Facts and Photos

What is Mookaite?

Mookaite is a colourful sedimentary rock from Western Australia, widely marketed, albeit incorrectly, as a variety of jasper.

Mookaite formed from the fossilised remains of tiny marine organisms called radiolaria. These single-celled plankton have silica-based skeletal structures, often intricate and spiny.

They drift with ocean currents, and over millions of years, their silica-rich remains settled on the ancient seafloor, compacting into what is scientifically known as the Windalia Radiolarite, the formation where mookaite is found.

Through natural geological processes, these sediments became heavily silicified, transforming into the durable, quartz-rich rock now called Mookaite.

Mookaite is a rock, not a mineral, because, like jasper, it's composed of a mixture of minerals and substances. It typically contains silica, clay minerals, and varying concentrations of iron oxides and manganese, which create its striking colours, including shades of red, yellow, brown, cream, and purple.

Mookaite is mainly used for decorative purposes and its metaphysical healing properties. Along with precious opal, it's one of Australia's best-known gemstones.

Mookaite grades 6 to 7 on the Mohs scale, which is relatively hard. However, it's also brittle, so can break or fracture easily.

The Name 'Mookaite'

The name 'Mookaite' comes from where this sedimentary rock is found. Although Mookaite is a trade name, it has never been officially registered.

It's common for the suffix 'ite' to be used when naming rocks and minerals. Trade names usually include the location where a material is found, the person who discovered it, or another identifying characteristic. Labradorite, sugilite, charoite and shungite are a few examples.

Many online articles claim that the name 'Mookaite' comes from an Aboriginal word meaning 'running waters.' However, this translation is not consistently supported by linguistic research or primary sources, and no widely recognised Aboriginal language dictionary explicitly links the two.

Aboriginal languages are highly diverse, with hundreds of distinct groups across Australia. The specific language group associated with the Mooka Creek area is not always clearly identified in discussions about Mookaite.

The Mookaite deposit is on private land at Mooka Creek, within Mooka Station, on the western side of the remote Kennedy Range National Park. This type of stone has not been found anywhere else in the world.

Although often pronounced 'mookite', the correct pronunciation is 'mooka~ite' because the stone was named after Mooka Creek.

Mookaite Versus Jasper

Mookaite is often described as an 'Australian Jasper', which is incorrect. Although the difference between Mookaite and Jasper is minimal, they're different types of rock.

Both are silicified, meaning they're rich in silica. They're also opaque, usually colourful and can be highly polished.

The key difference is the type of silica. Jasper is uniformly microcrystalline quartz, known as chalcedony. Mookaite contains a mix of silica types, from opaline, which is non-crystalline, to chalcedonic, which is microcrystalline, meaning its crystals are too small to be seen with the naked eye.

To many, this may not seem important, but in geology, it matters.

Although Mookaite is slightly different, it shares many of the characteristics that make jasper so popular.

In commercial contexts, particularly in the crystal healing, gemstone, and decorative markets, ‘jasper’ is a familiar and widely recognised name. Calling Mookaite an ‘Australian Jasper’ makes it easier for sellers and buyers to categorise and promote, alongside other colourful, highly polished stones.

Most people buying crystals or decorative stones focus on appearance and texture, rather than the correct geological names. The name ‘jasper’ also sells far better than ‘silicified radiolarite’.

Historically, once dealers, miners, and lapidary artists began using the name ‘jasper’ to describe stones that resembled jasper, the name stuck. The crystal market continued using this name not only for Mookaite, but also for other stones like ‘zebra jasper’, ‘leopardskin jasper’, and ‘kambaba jasper’, all of which are not true jaspers.

This happens because there isn’t a global regulatory body to enforce naming standards for popular rocks and minerals. As long as a name isn’t significantly misleading, the market tends to accept geologically inaccurate trade names, of which there are many.

Article Pictures

The Mookaite in the picture at the top of our page is courtesy of James St.John.

The Mookaite in the second photo and the tumbled stones are from our collection.

Pictures 1 and 3 are clickable. Picture 1 redirects to an entire album of Mookaite.

Pop-up photo: Opal: Courtesy of Stan Celestian.