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 Post subject: Opal mining in Coober Pedy
PostPosted: Sun Jan 22, 2006 8:36 pm 
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Coober Pedy Opal Mining

Just returned from a holiday around South Australia, where I was lucky to spend a few days in the Opal Mining Capital of Australia, Coober Pedy. This fascinating place is the closest thing you can imagine to a space port on a dry and distant planet, and for anyone visiting Australia is a must see destination.

All mining is undertaken in very small teams of mostly 1-2 operators, or small syndicates, and there are no real commercial mining companies there. The Opal seam is generally 13ft underground, and to find the seams, the miners dig a 20ft+ deep circular hole in the ground about 3 feet across. They examine the material coming out, and if there is nothing to be found, they move over 10ft, and try again. This creates hundreds of thousands of small piles of ground up lime and sandstone, which litter the landscape like some strange moon.

When material is found, they dig outwards, to a maximum of (I think) 60 meters from the initial shaft. They have an interesting digging machine that cuts away the rock, and a huge vacuum that drags the crushed rock to the surface, where it is examined for traces of Opal. Once a seam is found, it is dug out by hand, to make sure they get the large seams intact, as they are worth more this way.

This does however leave piles of crushed rock next to the mines, full of smaller pieces of opals, which are not of interest to the miners. This has spawned a secondary mining industry called noodling, and is usually carried out by individual crawling over the piles of rock and hand picking opal or potch (opal with no play of colour that is used to back doublets and triplets).

Some noodlers are more professional, and have created home made noodling machines, which wash and sort the crushed rock, and pass them along a conveyor belt in a darkened tent under black light. As opal fluoresces under UV, the opals are easy to pick out.

Only a handful of miners make in excess of $1 million a year. 30-40% are estimated to make a “good living” with another 30-40% making an okay living. They rest generally are struggling or just making ends meet.

My family and I spend in total less than 3 hours noodling for fun, and between 4 adults and three children, managed to extract a couple of small bags of rough opal and potch from the piles. One of the local buyers offered us $1,800 for our entire parcel, and individual offers of $350 and $400 for 2 individual stones. I am not sure if we were extraordinarily lucky or not, or if knowing one of the buyers good friends helped, but to me, that is a fantastic few hours spent. Even my 8 year old son was offered $80 for his prize find, although he declined and kept it as a souvenir to show his friends. All of us declined to sell, however it was nice to get an idea pf price.

I have a attached a few shots to give you an idea.

Here are the children noodling madly…
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Here is the vacuum machine that sucks the crushed rock back to the surface, creating the piles of rock.
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Here is a noodling machine.
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And this is what it is like underground. A welcome 23 degrees, althoughy outside it is 44!
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Martin


Last edited by Martin on Mon Jan 23, 2006 6:27 pm, edited 1 time in total.

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PostPosted: Sun Jan 22, 2006 9:31 pm 
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Thanks for sharing your "vacation" with us, Martin :D . Sounds like everyone had great fun! I was beginning to wonder why the miners weren't made to put the dirt back in the holes, but I guess the noodle-ers don't mind :lol: . I'll have to put noodling on my list of things to do if I ever get to Australia.


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PostPosted: Sun Jan 22, 2006 11:55 pm 
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The township of Coober Pedy was for many years "out of jurisdiction", which basically means it does not fall under any council governed areas. This made it a bit of a "anything goes" kinda town, and even over the last few years the court house was blown up. Stories of machine gun patrols guarding against claim hopping are also still recent memories, although since the town was properly incorporated, it has been cleaned up extensively.

As for filling the holes back up, Coober Pedy is a town that has prospered due to the mining, and did not exist before Opal was found there. They were basically holes in the desert - why would you fill em in? Several hundred kilometres from any civilisation, and almost 850 Kilometres from Adelaide, the nearest city.

Over recent years however, and a few tourists falling down mine shafts, the mine sites have been fenced off, and tourists are not permitted to enter the working mines. Instead large quantities of mine spoils have been dumped into safe places for noodling by tourists and casual noodelers. The largest producing mine areas is the Olympic mine, which is reported to be 20kms long, and 8kms wide.

Out of interest, when the earlier miners came, they dug holes in the hill sides to live in, as the caves they created were a constant 23-25 degrees all year round. Coober Pedy is derived from the aboriginal kupa piti which means “white men in holes” or “white mans burrow”. It is common for people to live in these “dug outs”, and some even have swimming pools inside of them. As mining within the township is now banned, many people “extend” their dugout to have very large “extra rooms”, and are often lucky enough to find more opal in doing so.

I stayed at the desert cave, which is an underground hotel in the dugout style. The manager told me that in digging out the hotel, they found enough Opal to pay the entire construction costs, and hinted that the hotel was simply a front for illicit Opal digging – although this could of course be tourist gossip.

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PostPosted: Tue Jan 24, 2006 6:06 am 
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The new generation of "Martins" sure look like they have caught the bug of dad, great to see we really need to promote Gemology as something exciting for all. Your trip sounds very interesting, Lighting ridge next?
Dont forget Reddestone creek if you ever get the chance.
Cheers Andrew

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PostPosted: Tue Jan 24, 2006 5:08 pm 
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Andrew - they sure have - it's in the blood. Redstone creek was on my trip notes, but when my parents realised the vastness, the plans had to be scaled down a bit.... :-(

But I will get there some day...

Martin

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