Item Information

Dimensions (mm) 35 x 15 x 6mm
Weight (carats) 22 carats


Opal type     Natural Boulder Opal Rough                
Origin     Winton, Queensland, Australia    
Size         35.00 mm x 14.80 mm x 6.30 mm      
Weight     22.40 cts            
Colour     reds / orange / yellow / blues / greens / purple      
Pattern      -       
Brightness rating  1 to  5      4.3          

Additional information      This raw 'fairly opal' rough shows glorious bright pinfire colors and is yet to be treated.  To view some treated stones on this site look in Boulder Opal > Boulder Opal Matrix, and type in the keywords box on the left  ' fairy ' .

 In its current state it will not take a polish and I have left the experience of treating the stone for others to enjoy.   Called 'carbonising', it is a very fun simple procedure requiring not much more than sugar, sulfuric acid and a kitchen stove.  For the novice there is plenty of information on the internet and if you require I can help point you in the right direction.  I will place a few of these items on this site.  Should anyone wish to treat a few at the same time you will only be charged the one shipping fee if shipped at the same time.  You can see the bright pinfire color in these stones, seeing them come to life during treatment is quite enjoyable.  

This is a high quality piece with bright pinfire and clusters of flashing.

Item(s) have been precut to 5 – 10mm thick approx. and carefully rubbed back to expose the color.  Rough items are photographed wet to give a more accurate appearance of the stone and color when polished.

In most cases more opal will be revealed during cutting. All items are genuine and untreated unless clearly stated in the above description section.



 some    ' Helpful Hints '  on selecting rough                   

For those not greatly experienced in buying rough here are some basic 'general' formulas that may help.    note :  ( 5 carats  =  1 gram)

     #1     Untouched raw rough, only washed clean in an agitator for instance and not rubbed,  you should expect the final cut stone to be around 20% of the rough piece.  For example.  A 5 carat untouched rough should cut approximately a 1 carat stone, on average.

     #2     To guage if rough is priced attractively the previous 5 to 1 formula can be reversed.  For example.  An untouched rough piece bought for $10 per gram, applying #1, would give you a cost of $10 per carat for the finished stone.  #2 is then applied showing that, 5 x your original $10 per carat cost, you should be able to purchase an equivalent cut stone for $50 per carat.  ( An equivalent finished stone should be approximately 5 to 1 or 5 x your cost )

     #3     Rubs or rubbed stones that have been worked on to expose the color offer a far less risk or gamble when purchasing as you can see more easily what you are buying and also a dealer knows exactly what they are selling.  There is much less waste material and a far greater yield than buying untouched rough as in example #1, hence the cost per gram for rubs is much more.  (often between 40 - 60% of the finished stones' value)  Once you determine the cost of an equivalent cut stone you can then determine if the work left to finish the stone is worthwhile.

The above three points are an average, general, basic guide and will differ from dealer to dealer and rough to rough as 'opal always surprises'.  Sometimes rough that shows little or no visible color to anyone can yield a nice stone within and unfortunately this can work the opposite way too.  A reason why cutting and orientating opal is interesting and so much fun.  Another point to consider is whether you will be cutting conventional stones or freeforms which will increase your yield. 

And when purchasing boulder opal you must also consider that it is commercially acceptable to have ironstone or host rock exposed on the face of the finished stone.

There is no substitute for common sense and logic, this of course comes with our own personal cutting experiences.  Luckily we have advanced through the mail order catalogue times and fantastic sites like this offer us pictures to view the actual items before we buy.  However, with opal, nothing can compare with seeing it in your own hand, in natural sunlight and when you first receive a rough parcel you should always wet it and view it this way.  Lastly, always insist on a 100% Money Back Guarantee.   All good dealers who believe in their product and service know that not all rough opal is suitable to everyone, and will offer this, happily !  


" Guarantee "       

OutbackOpal's rough items are priced extremely fairly with the above hints in mind and in accordance with the wholesale guidelines of this great auction site.  The items you will receive are the items that are pictured and all opals are represented as accurately as possible.  However, it can happen that one cutters challenge can be another cutters nightmare.  So if your opinion varies and you are not happy with your purchase, you are welcome to contact us to organise a prompt safe return and refund for the entire, unused and unaltered product.  Which is no less than I would expect when making a purchase !



I am as excited about these gems today as when I started working with them over 15 years ago. My name is Andrew, and my fascination with opals started back in 1992. Since then I have been involved with cutting, crafting and selling these ‘little Aussie beauties’ and the years have seen me work for several multi national companies.
Personally, I have only ever mined opal for fun, as a hobby, with friends and associates who own and work leases in western Queensland and Lightning Ridge areas.  These products for sale here are directly from them, the hard workers in the field.   
Should you ever feel that the product you receive is not what you expect please feel free to contact me at your earliest convenience. You will receive a reply within 48 hours from me or a representative from my opal family to discuss any concerns and your prompt replacement.
Best of luck with your opal endeavors!





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Pricing & Details

Bid Increment $1.00
Starting Bid $17.00
Auction ID 173536
Watchers 2 watching
Viewed 1,525 times
Starts 19th Oct 2016 9:08am PDT
Ends 22nd Oct 2016 9:05am PDT

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