Prospecting for opal in Australia
General
Does someone in your family own a ring or pendant that contains an opal? An opal is a 'gemstone' - that is, a mineral valued for its beauty. Gemstones are most often used in jewellery and examples include diamonds, rubies, emeralds, sapphires, jade, opals and amethysts. Gems generally get their colour because of certain metals contained in the mineral (for example amethyst is quartz containing tiny amounts of iron) however opals are unique because they display many different colours.Properties
Uses
Opals are used in jewellery and ornaments.
Photo courtesy of NSW Department of Primary Industries
Source
Photo courtesy of Office of Minerals and Energy Resources, PIRSA
Opal is found around the world (Brazil, Mexico, Honduras and the western US) however Australia produces 95% of the world's precious opal.
White opal was first mined commercially at Listowel Downs in Queensland in 1875. Today, Coober Pedy (SA) is the main white opal centre, Lightning Ridge (NSW) the world's only source of black opal, and boulder opals are mined in Central Queensland.
Opal is one of the few minerals which can be mined economically by a miner working alone.
The miner digs a shaft using a pick and shovel, uses explosives or a pick to dig out earth sideways from that, then uses a small hand-pick or even a screwdriver to extract any opal traces found.
'Noodling' is when people search through old mullock heaps (see left) for pieces of opal that might have been missed in the initial mining operation.
However, since the 1970s machines have been gradually taking over from hand mining methods, along with the use of radar and electric currents to find possible opal-rich areas.
Once mined, opal ore is then sifted to separate the hard material, which is then tested for any signs of colour.
After that, opal sorting is done by hand and requires a keen eye to see for signs of 'colour in the rough'.
The immigration online verification service will be used to confirm the status of all international passports prior to a permit being issued.
Andamooka
Coober Pedy
Mintabie
Stuart Creek
Lambina and Welbourn Hill
Photo courtesy of Office of Minerals and Energy Resources, PIRSA
Although there is no restriction on tourists accessing the proclaimed opal fields at Coober Pedy, Mintabie, Stuart Creek and Andamooka, it is not recommended because of the many open shafts, deep bulldozer cuts, heavy machinery and use of explosives.
If you want to visit the opal fields, it is recommended that you use a recognised tour operator. For more information visit the local tourist information centres.
Opal was discovered in Andamooka in 1930. The Andamooka opal field covers an area of 263 square kilometres. It surrounds the town, located approximately 35 km east of Roxby Downs and approximately 250 km north of Port Augusta via Woomera.
Accommodation may be found in Andamooka and Roxby Downs.
Discovered in 1915 the opal fields cover an area of 4954 square kilometres, located on the Stuart Highway 550 km north of Port Augusta.
Coober Pedy is a modern town with all amenities and tourist facilities.
Located on the Anangu Pitjantjatjara Yankuntjatjara Lands 32 km west of Marla, the Mintabie field was originally discovered in 1929 and covers an area of 213 square kilometres.
Access is restricted under the Anangu Pitjantjatjara Yankunytjatjara Land Rights Act 1981. A permit to travel to Mintabie township can be obtained from Marla Police Station.
As a result of the Anangu Pitjantjatjara Yankunytjatjara (APY) Land Rights (Mintabie) Amendment Act 2009 which came into operation on 1 July 2012 changes have been made to the Opal Mining Act 1995. These changes to Precious Stones Prospecting Permits and to Precious Stones Tenements on the Mitabie precious stones field. More information about these changes
Discovered in 1947, the Stuart Creek opal field covers an area of 25 square kilometres, approximately 58 km north of Andamooka. It is a remote waterless area without any significant shade trees, requiring a 4WD vehicle for access.
Stuart Creek opal field is only recommended for experienced opal miners and bush travellers.
It is not recommended that tourists travel to Lambina and Welbourn Hill.
There are six negotiated diggings over the two pastoral stations. Access is by service of Notice of Entry to genuine opal miners.
See Earth Resources Information Sheet M08: Prospecting and mining for opal outside proclaimed precious stones fields (.pdf 4.7Mb) for more information about the requirements to enter these areas.
White opal was first mined commercially at Listowel Downs in Queensland in 1875. Today, Coober Pedy (SA) is the main white opal centre, Lightning Ridge (NSW) the world's only source of black opal, and boulder opals are mined in Central Queensland.
Opal is one of the few minerals which can be mined economically by a miner working alone.
The miner digs a shaft using a pick and shovel, uses explosives or a pick to dig out earth sideways from that, then uses a small hand-pick or even a screwdriver to extract any opal traces found.
'Noodling' is when people search through old mullock heaps (see left) for pieces of opal that might have been missed in the initial mining operation.
However, since the 1970s machines have been gradually taking over from hand mining methods, along with the use of radar and electric currents to find possible opal-rich areas.
Once mined, opal ore is then sifted to separate the hard material, which is then tested for any signs of colour.
After that, opal sorting is done by hand and requires a keen eye to see for signs of 'colour in the rough'.
Information for tourists
Note: Visitors from overseas who wish to apply for a Precious Stones Prospecting Permit must have an unlimited working visa.The immigration online verification service will be used to confirm the status of all international passports prior to a permit being issued.
Andamooka
Coober Pedy
Mintabie
Stuart Creek
Lambina and Welbourn Hill
Amazing Facts
- Opals are multi-coloured.
- Opals consist of small spheres of silica arranged in a regular pattern, with water between the spheres.
- The spheres diffract white light, breaking it up into the colours of the spectrum. This process is called 'opalescence'. Larger spheres provide all colours, smaller ones only blues and greens.
- White opals have delicate, pale colours on a lighter background.
- Black opals (very rare and valuable) have a dark background and colours ranging from brilliant red through to greens, blues and purples.
- Boulder opals are cut with the natural host rock, ironstone, on the back.
- Opals have the same hardness as glass (5.5 - 6.5)
- If you move the stone, light hits the spheres from different angles and brings about a change in colour.
- Opal comes from the Greek opallos meaning 'to see a change (of colour)'
- Opal artefacts several thousands of years old have been discovered in East Africa.
- As early as 250 BC the Romans prized opals, thought to have come from mines in eastern Europe, the world's main source of opals until 1932 when Australia took over as the major producer.
- In 1915 a group of people were prospecting for gold at the edge of the Great Victoria Desert Northwest of Adelaide. Making camp one night, a 14 year old boy found an opal. This started an 'opal rush' and soon the settlement of the Stuart Range Opal Field was founded.
- Today's main white opal centre is the town of Coober Pedy, whose name comes from the aboriginal name Kupa Pita, which means 'White man in a hole or burrow'.
- In Coober Pedy many people have built their homes in old mine shafts (calling them dugouts) or in low hills because in summer the temperature goes over 50 degrees Celsius.
Photo courtesy of Office of Minerals and Energy Resources, PIRSA
Although there is no restriction on tourists accessing the proclaimed opal fields at Coober Pedy, Mintabie, Stuart Creek and Andamooka, it is not recommended because of the many open shafts, deep bulldozer cuts, heavy machinery and use of explosives.
If you want to visit the opal fields, it is recommended that you use a recognised tour operator. For more information visit the local tourist information centres.
Opal was discovered in Andamooka in 1930. The Andamooka opal field covers an area of 263 square kilometres. It surrounds the town, located approximately 35 km east of Roxby Downs and approximately 250 km north of Port Augusta via Woomera.
Accommodation may be found in Andamooka and Roxby Downs.
Discovered in 1915 the opal fields cover an area of 4954 square kilometres, located on the Stuart Highway 550 km north of Port Augusta.
Coober Pedy is a modern town with all amenities and tourist facilities.
Located on the Anangu Pitjantjatjara Yankuntjatjara Lands 32 km west of Marla, the Mintabie field was originally discovered in 1929 and covers an area of 213 square kilometres.
Access is restricted under the Anangu Pitjantjatjara Yankunytjatjara Land Rights Act 1981. A permit to travel to Mintabie township can be obtained from Marla Police Station.
As a result of the Anangu Pitjantjatjara Yankunytjatjara (APY) Land Rights (Mintabie) Amendment Act 2009 which came into operation on 1 July 2012 changes have been made to the Opal Mining Act 1995. These changes to Precious Stones Prospecting Permits and to Precious Stones Tenements on the Mitabie precious stones field. More information about these changes
Discovered in 1947, the Stuart Creek opal field covers an area of 25 square kilometres, approximately 58 km north of Andamooka. It is a remote waterless area without any significant shade trees, requiring a 4WD vehicle for access.
Stuart Creek opal field is only recommended for experienced opal miners and bush travellers.
It is not recommended that tourists travel to Lambina and Welbourn Hill.
There are six negotiated diggings over the two pastoral stations. Access is by service of Notice of Entry to genuine opal miners.
See Earth Resources Information Sheet M08: Prospecting and mining for opal outside proclaimed precious stones fields (.pdf 4.7Mb) for more information about the requirements to enter these areas.
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