The Discovery of Opal

In January 1915 – 100 years ago – a small group of men named the New Colorado Prospecting Syndicate had unsuccessfully been searching for gold just south of Coober Pedy.

On February 1, they had set up camp and were searching for water when the 15 year-old (William Hutchison) son of one of the men found pieces of surface opal. Eight days later, the first opal claim was pegged.

Due to lack of water and the extreme heat, the party left on February 18th and headed to William Creek. A few months later, the O’Neill brothers & Fred Blakeley arrived and became the earliest opal mining pioneers and introduced the unique method of living underground in “dugouts”. The flies were bad and there were no building materials.

In 1917, the Trans Continental Railway was completed and a number of construction workers came to the opal fields. They were followed by soldiers returning from the First World War. Conditions were harsh and water and provisions had to be carted great distances and under very trying conditions.

During the Great Depression of the late 1930s and 1940s, opal prices plummeted and production almost came to a standstill. But then, typical of Coober Pedy’s history of boom and bust cycles, an Aboriginal woman named Tottie Bryant made a sensational opal find at the Eight Mile field in 1946 starting a new rush to the fields. During the 1960s, the mining industry expanded rapidly as many European migrants came to seek their fortunes. Opal mining developed into a multi-million dollar industry and Coober Pedy became a modern mining town.


Where Opal is today in Australia

Australia has 95% of the world’s supply of commercial opal and the largest percentage still comes from the 70 opal fields around Coober Pedy.

Opal is a true precious stone composed of amorphous silica and water. 85% of all opal found is called potch (opal without fiery colours) which has little value. It is the other 10% of vividly coloured opal that qualifies as the precious opal admired throughout the world.


Miners, with a Mining Permit, can peg a claim either 50m x 50m or 50m x 100m to mine for opal.

The earlier form of mining was by sinking or digging a shaft then tunnelling along the level with a pick and shovel. A hand-pick or screwdriver was used when traces of opal were found.

Since the 1970’s, there has been a rapid increase in the use of mining machines. These days, most if not all prospecting shafts are made by using a Calweld-type drill which is used to excavate holes about one metre in diameter using an auger bucket. The drills can dig to a maximum depth of about 28m to 30m.

Today’s opal fields are subsequently pitted with thousands of abandoned Calweld shafts.

Tunnelling machines with revolving cutting heads and small underground front-end loaders called boggers are used while bulldozers are employed to remove overburden and expose the level where it is shallow.

Spotters follow behind watching for opal and the seam is then worked over by hand-pick.

Waste material (or mullock) from the shafts and drives was originally lifted to the surface by hand windlass, then by power winches (Yorke hoists) or automatic bucket tippers.

Solid opals that naturally occur in one piece.

Doublet a 2 part stone consisting of a precious opal glued to another stone, either potch or some other material like glass or iron stone.

Triplet a three part stone with a precious opal centre, a clear top and darkened base, usually glass or potch.

Opal Processing & Classing

Once the rough or raw opal has been mined it is placed in a small water-filled tumbler or a cement mixer. The agitation cleans about 95% of the dirt (sandstone) from the rough opal and whatever dirt remains is then snipped off.

The opal is sorted or classed in different grades by size and of course colour and quality. Colour in precious opal is caused by the regular array of silica spheres diffracting white light and breaking it up into the various colours of the spectrum.

There are a number of things to assess when classing opal colour. These include the quality, brilliance, clarity, variety and pattern.

The main factors in determining the price paid for opal are as follows.

Base Colour. Black opal (a gem with a dark base) is more valuable than crystal opal (almost transparent) which in turn is more valuable than the white or milky opal.

Dominant Colour Red fire opal is more valuable than a predominantly green opal, which in turn is more valuable than a stone showing only blue colour.

Colour Pattern Harlequin opal, where the colour occurs in defined patches, is generally more sought after and valuable than pin-fire opal where the colour generally appears in small specks.

Once the opal has been classed in various grades, each grade is weighed in Troy ounces then valued at a rate of dollars per ounce before being placed into a bag.

Each bag is then identified by grade and weight. Collectively these bags are known as a PARCEL of opal.

Cut opal is valued at a price based on quality, brilliance, clarity, variety of colour and pattern per carat weight. Opals may be cut and polished in a number of ways, depending on the nature and thickness of the colour band.

Opals are the softess of the precious gems and need delicate care when shaping and polishing a stone. Always ensure your jeweller is familiar with opal when taking your jewellery for polishing.


Noodling is the process of searching through heaps of discarded mullock for pieces of opal missed by the miners. Many locals make a living from this method and it is also very popular with tourists.

Noodling machines, in which mullock is passed through a darkroom on a conveyor belt beneath ultra-violet lights are also used, and this is another form of mining.

Some people get lucky and find their fortune, others find little chips to keep for memories. Have a look around town, most of the stores have little noodling pits & little bottles of chips for purchase.

Where did the term “Noodling” come from?

Who really knows, the urban myth says that it comes from the term “wet noodle” A man who does not have the courage or is not strong/powerful or ‘man’ enough to mine for opal underground was called a “wet noodle”. This ‘wet noodle’ looks for opal on the surface where it is safe. So maybe not a nice term but an amusing one!

Opal Displays

Coober Pedy shops have more opal on display than anywhere else in the world. You will find different types of opal from all around Australia, so all you need to do is shop around for your special choice. All reputable shops will guarantee their opals in writing. Some shops also offer opal cutting demonstrations.

Opal Display & Sales Locations

Desert Soul Jewellery

Designing and making custom jewellery. Repairs • Ring resizing • Opal, Diamonds and all precious…

Fossil Creations

Why not come and see our selection of Andamooka Matrix Opal and Coober Pedy Opal.…

Desert Cave Hotel

Desert Cave Hotel, the only International underground Hotel, allows you to experience dug-out style living,…

Opal Direct

In the Centre of town – come and view our extensive range of opals. Contact…

Star Opal

A family owned business. For all your opal, art and lapidiary supplies. Contact Details ADDRESS:…

Opals on Hutchison

A family owned business with over 40 years experience in mining, exporting, designing and manufacturing…

Gaea Gems

Gaea Gems (Earth Gems) is a modern opal shop with fantastic souvenirs and indigenous art…


It’s been 44 years and we have so many wonderful memories and stories about Coober…

Umoona Opal Mine & Museum

Learn about mining and living underground in Coober Pedy with our informative tour and experienced…

Tom’s Working Mine

NOTE:  Tom’s is currently closed for renovations – due to open early 2021.   Large…

Old Timers Mine

Winner of many tourism awards including the South Australia Heritage and Cultural tourism award. Opal…

Josephine’s Gallery

Discover the unique aboriginal art and local artifacts. Visit our Kangaroo Orphanage. Feeding times 12:00pm…

Waffles & Gems

Waffles & Gems is a Cafe, Jewellery & Local Arts & Craft Shop situated in…

Opal Cave

Opal Cave provides the most interesting, unique and informative stopover on your entire trip with…

Radeka’s Downunder

Radeka Downunder Underground Motel and Backpacker Inn is located in the centre of Coober Pedy,…

“For in them you shall see the living fire of ruby,

the glorious purple of the amethyst,

the sea green of the emerald,

all glittering together in an incredible mixture of light”

Written by Roman Pliny in the 1st Century AD