Australia’s ancient landscape hosts rock formations dating back billions of years, making it an important location for geological research. Australia is home to hundreds of varieties of gemstones; however, a few gemstones have become a unique part of the country's history.
Australia has long been renowned as one of the top sources of opal in the world. This gemstone features a wonderful 'play-of-colour' effect, a unique display resulting from the diffraction and interference of light caused by the silica spheres in its structure.
Opals can exhibit a rainbow effect of colours, from the more common blues to green hues, to the highly desirable orange to red. The presence of strong red hues is referred to as the opal's 'fire' and can give contrast and life to the gemstone. Opal has been commercially mined in Australia since the Victorian era, when the discovery of gold fields sparked a goldrush.
Opal deposits were first discovered in 1849 by Johannes Menge near Angaston in South Australia. Opals of all varieties, including fire opal, crystal opal, boulder opal, white opal and the highly prized black opal, have continued to be mined from Australia.
Major opal producing regions include Coober Pedy, Lightning Ridge, Andamooka, and Winton. The significance of the opal deposits of Australia was formally recognised in 1993 when opal became the country's national gemstone.
Pink Diamonds
Diamonds have been mined in Australia since the mid-1800s, making it an important world source. However, it wasn't until the late 1970s when prospectors in the Kimberley region discovered diamond deposits that would become the Argyle Mine.
When it transitioned to an open-pit mine in 1985, the mine became a leading source of pink diamonds, once producing 90 per cent of the world's natural pink diamonds.
The Kimberley region's geological composition is diverse compared to other known diamond deposits. The gemstones are encased in a host rock of lamproite, as opposed to the more common kimberlite.
The Argyle Mine closed in 2020 due to depleted supply, causing pink diamond prices to surge.
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| Australia is the source of many of the world's finest gemstones, including opal, diamonds, sapphire, and pearls. |
Sapphire
The discovery of blue sapphires in Australia occurred as a by-product of the 1850s gold rush; however, mining efforts on a commercial scale didn't begin until the early 1900s.
The ancient landscape of the New South Wales region comprises thousands of square kilometres of volcanic rock, which hosts various sapphire deposits. Due to their high iron content, Australian blue sapphires typically have a darker blue colour.
Another variety of sapphires is the parti coloured stones, which have a renowned blue to yellow-green colour banding.
These distinct gemstones have gained popularity and become a fashionable option for engagement rings over the last decade.
Central Queensland has been an important source of sapphires in Australia for more than a century, with production elevated during the 1980s.
Sapphire from this region occur from secondary deposits; alongside sapphire, zircon and diamond.
South Sea Pearls
Australia is a renowned source of South Sea pearls and produces some of the world’s finest. The large oyster variety, the Pinctada maxima, was first discovered by divers off the north-west coast of Australia in the late 1800s.
The Australian cultured pearl industry began operations in 1906 with the cultivation of blister pearls.
Economically successful production of whole cultured pearls was achieved after World War II, and by the 1950s, the first Australian pearl farms were established. The town of Broome became the centre for industry, and the pearls were originally dubbed ‘Broome pearls’.
By the 1990s, South Sea pearl production could keep up with the demands of large jewellery retailers, and the popularity of Australian South Sea pearls increased. Today, Australian South Sea pearls are one of the most sought-after pearl varieties in the world.
Something for everyone
Australia's ancient and diverse landscape enables a large variety of gemstones to form. The country's production of opals, pink diamonds, sapphires, and South Sea pearls has become world-renowned.
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