Andamooka is a major opal mining area in South Australia famous for producing stunning, rare opal varieties like Andamooka crystal opal and matrix opal.
Like most Australian specimens, Andamooka opals have a reputation for high quality. In fact, Andamooka matrix opals are some of the best matrix opals in the world. Plus they’re porous, so jewelers can use sugar treatments to darken the background and enhance the vibrant play-of-color.
The Australian town is also famous for gorgeous crystal seam opals, “painted lady” boulder opals, and even prehistoric opalized dinosaur fossils.
FAQs
What is Andamooka matrix opal?
Matrix opal is a variety of opal intimately mixed with its host rock. The iridescent opal material fills veins, voids, or pores between the grains. Andamooka matrix opal, nicknamed “kopi” by locals, features bright precious opal replacing limestone host rocks in small patches.
Where is Andamooka opal found?
Andamooka opal comes from the small town of Andamooka, around 600 km (~370 miles) north of Adelaide. Miners and even tourists find these opals in relatively shallow digs or search the ground after heavy rain to unveil the buried gems.
Are Andamooka opals rare?
Some are. Black opals from Andamooka are extremely rare, and most have been treated to be black. High-quality Andamooka crystal opals have been getting rarer.
What is the difference between Andamooka matrix opal and Andamooka crystal opal?
Andamooka matrix opals have opal material intimately mixed with their host rock, often limestone or quartzite, the latter being famous for hosting the Andamooka rainbow matrix opal variety.
Crystal opals are semi-transparent to transparent with almost any body tone but most prized with vibrant play-of-color. Andamooka crystal opals may be within matrix opals, a valuable pairing.
What is the history behind Andamooka opals?
Nearly 60 years after Europeans settled in Andamooka, two boundary riders (cattle employees) named Sam Brookes and Roy Shepperd were escaping a storm in 1930 and stumbled upon an opal deposit on what’s now called Treloars Hill.
Local miners found other deposits and word spread about the discovery. Various folks flocked to the area to cash in on opal mining or enjoy the wilder outback lifestyle. Since 2014, the major pastoral leases have been granted to Kokatha Pastoral Company, owned by the native Kokatha people.
\What is the royal Andamooka Opal?
The famous Andamooka Opal or “Queen’s Opal” is a white opal mined in 1949 and cut by John Altmann into a 203-carat cabochon. It was presented to Queen Elizabeth II in 1954 when she first visited South Australia.
The stunning opal was set in an 18K palladium choker with 180 accent diamonds and matching Andamooka white opal earrings.
Can Andamooka opals be used in jewellery?
Absolutely! The royal Andamooka Opal set is a perfect example, but you can use the stone for other jewelry too, like a simple Andamooka crystal opal ring or statement Andamooka matrix opal necklace.
How can I identify Andamooka opal?
One clue when identifying Andamooka matrix opals is to see if the host rock is porous. These are often treated to look like black opals and should be sold as “treated Andamooka matrix opal.” If not, you can use a loupe to look for small black carbon inclusions in the matrix indicating the treatment.
When in doubt, it’s best to have a professional third-party appraisal and authentication.
What makes Andamooka opal valuable?
They’re not extremely valuable, but some of the highest-quality matrix opals and crystal opals come from Andamooka. Andamooka crystal opals and matrix opals with brilliant play-of-color, multiple color flashes, and little to no visible inclusions are most valuable. Treatments will lower the value of Andamooka matrix opal.
How should Andamooka opals be treated and cared for?
If your opal is thin, you should only have it set in less vulnerable jewelry like a pendant instead of a ring. Andamooka opals are porous, so don’t soak them in water and keep them away from other substances like oils or cleaning solutions.
Only clean these stones with a soft cloth, mild soap, and warm water. Fully dry them before storing your opal in a cloth bag or velvet-lined box away from extreme temperature changes or humidity.
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