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All of the significant opal deposits in Australia during the last 100 years are located within or surrounding the Great Artesian Basin. The most important deposits are found in New South Wales, South Australia and Queensland.
Today, mining is carried out at the following main areas and each area produces solid opal with specific characteristics and colour patterns.
Lightning Ridge, New South Wales
This is a town famous for its rich and rare black opal. Black opal gets its name from the colour of the “nobbies” or pieces of rough opal in which the gems are usually found.
Black opal was first discovered here in the late 1880’s, however its commercial value was not at first recognised by buyers. It wasn’t until the early 1900’s that some opal nobbies were found and shafts dug.
Opal occurs either as “nobbies” or in seams and thin layers within a soft greyish clay stone. The opal dirt levels occur between six and eighteen metres from the surface, but have been found at depths as deep as thirty metres. The fields also yield opalised shells, wood and reptilian bones.
Some of the traditional fields around Lightning Ridge include the Three Mile and Thorleys Six Mile.
White Cliffs, New South Wales
Located 295 kilometres northeast of Broken Hill, White Cliffs is Australia’s oldest opal field, where mining began about 1889. As with most towns with mining operations, the population quickly soared, peaking at 5,000 in its heyday.
The light crystal opal found at White Cliff quickly became famous on the world market. The opal fields produced the first commercially accepted opal, far surpassing the quality of the Hungarian mines, as opal displaying such vivid colours had never been seen before.
Between 1903 and 1914, the richer areas of the opal field became exhausted and a decline in production resulted. The effects of World War 1 also affected the area, contributing to the decline.
Central Queensland
The history of opal in Queensland dates back to the early 1870’s, but it wasn’t until 1889 when the gem was successfully marketed. The real development of the vast opal deposits began in 1873 with the discovery of fine quality opal north of Thargomindah.
During those early years production was low as there was no ready market for the gem. It took the efforts and determination of an entrepreneur named Tully Woolaston to establish the industry.
Today, the Queensland opal fields cover an area in the southwest portion of the state, approximately 1000 kilometres long by 300 kilometres wide.
Coober Pedy, South Australia
The Coober Pedy opal fields were discovered in 1915. Producing white or milky opals, until recently, Coober Pedy was the main producer of precious opal. Today the opal fields encompass an area of approximately 45 kilometres.
The name “Coober Pedy” is derived form the Aboriginal word “kupa piti” which loosely translated means “white Man in a Hole.” An isolated and rugged location, Coober Pedy is frequented by freezing cold nights, days where the temperature soars above 40° C and is inundated by millions of bush flies. Too hot to live above ground, homes in Coober Pedy are made in underground burrows.
Mintabie, South Australia
The Aboriginals were the first to sell black opal from Mintabie at Coober Pedy after WW1 but kept the place secret for some time until eager miners discovered the opal field in the 1930’s. As a result of the remoteness of the area and lack of water, mining in the area was on a small scale.
Mining production greatly increased beginning in 1976 as heavy earth-moving equipment was brought in. The opal, sandwiched between layers of sandstone and rock below ground, are drilled or blasted through with explosives.
The Mintabie area is now producing very attractive, semi-black opal.
Andamooka, South Australia
Discovered in 1930, Andamooka is one of Australia’s most famous fields. Located 600 kilometres north of Adelaide but southwest of Coober Pedy in harsh desert country, Andamooka is derived from an Aboriginal name meaning “Large Waterhole.” It is the only town in Australia where the streets have no names.
I hope you have enjoyed learning aobut the discovery of Opal in Australia.
In part 4 we learn about how opal is mined and cut.
See you then
Best wishes and have a great day.
Stuart Bazga
www.kulpunyaopals.com
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