Psychedelic Wonderland of Colour - The World of Minerals

Article | Updated 6 years ago

In the Origins gallery of the New Museum you will see objects and stories from the beginning of our Universe, from the formation of our Earth and showcasing the mineral diversity of our State.

Western Australia has an incredible diversity of minerals and we have more than 30,000 mineral specimens in our Earth and Planetary Sciences collection.

Did you know the WA Museum started as a geological collection in 1891?

Our staff study minerals and rocks using a range of different tools including a very cool ‘petrographic’ microscope.

By applying polarising filters to the light (like those in sunglasses) they can see amazing colours and textures of the minerals.  These are created by the light interfering with the different crystal structures and chemical compositions of the minerals to produce distinctive colours. 

To see the psychedelic colours, our geologists glue a block of rock to a thin glass slide, slicing off as much of the rock as possible, then grinding the remainder down to a thickness of 30 microns (or 0.003 mm). When they do this many rocks become transparent and whole new worlds are revealed under the microscope.

These cololurful and beautiful worlds are the inspiration for an immersive experience visitors will walk through when they visit out Riches of the Earth display in the new Origins gallery.

Figure 1: This image shows olivine lamproite with brightly coloured olivine crystals from the Ellendale diamond mine in the Kimberley region of WA.

Lamproites and closely related kimberlites are unusual volcanic rocks that have come from depths of over 150 km sampling rocks and minerals from the Earth’s mantle, including olivine and sometimes diamond, as they travelled to the surface.

Figure 2: Two carat yellow diamond in lamproite from the Ellendale mine. We will be featuring our collections of Ellendale and Argyle diamonds in the Riches of the Earth section of the Origins gallery in the New Museum.

Figure 3: Another unusual igneous rock (formed from a molten magma) from the Kimberley region is the Cummins Range carbonatite. Carbonatites are primarily composed of carbonate minerals such as calcite and dolomite that contain calcium, magnesium, carbon and oxygen. This image shows twinned calcite crystals in a criss-cross pattern and a yellow hexagonal crystal of the mica phlogopite.

Figure 4: Along with the carbonate minerals carbonatites commonly contain apatite (a calcium phosphate). In this image we see pale grey apatite that has been overprinted by brightly coloured monazite, a phosphate mineral that contains large proportions of the rare earth elements. The rare earth elements are highly sought after for applications in high tech manufacturing such as mobile phone technologies. The rare earth element-rich rocks from WA, such as the Cummins Range and Mt Weld carbonatites, will be featured in the Origins gallery in the New Museum.

Figure 5: This image shows another apatite and monazite-rich rock from the Cummins Range carbonatite. The monazite at Cummins Range formed at temperatures of several hundred degrees celsius, 1200 to 20 million years ago.

The lamproites, kimberlites and carbonatites of the Kimberley region were all derived from deep within the Earth and rose to the surface along deep fractures in the Earth’s crust.

Figures 6a and 6b:

Microcline and albite (minerals containing sodium, calcium, aluminium and silicon) from Yinnietharra, WA.

Figure 7:

Brightly coloured chert (composed of tiny crystals of quartz) with the iron oxide hematite (appears black) that has been cut by a coarser grained vein of quartz, from Mt Goldsworthy, Pilbara, WA.

Figure 8:

Pink, lithium-bearing holmquistite with green hornblende in a schist from the edge of the Greenbushes pegmatite in southwest WA.