46 grams Andamooka rainbow matrix opal rough -[F9027]9

Item Information

Dimensions (mm) 60 x 42 x 16mm
Weight (carats) 231 carats
Filled Cavities or Fissure/Cobalt
Heat Treatment
We bought this from a miner who roughly treated it and only cut the gem pieces. There was 300 kilos in this parcel which took him years to collect. . As it is from different opal fields around andamooka you will find some variation in absorbency when treated.

This is a natural opal treated so it becomes black and is called Andamooka Rainbow matrix opal- .. You can cut as stones or leave as specimen or for carvings. but you will have to re treat if you take too much away. Check that there isnt another colour bar in the rough you can expose that may be better than the top.
You may see black spots which is usually blackened sugar which will come off. The miner has just roughly treated and rubed them down.
Mined in Andamooka Sth Australia
We have taken the photo of the rough wet! We have cut stones from this parcel which are listed in sedaopals.
All rough does have a element of a gamble as some may treat better then others but this has been treated to show what the colour will be like.
250 grams glucose,white castor sugar,pot or pressure cooker,plastic tweezers.
-Pre shape the material

- Thoroughly dry the material in oven sun or hairdryer. You can also soak in aceton for 10 minutes to dry the stones out.
- Put water in pot on low temperature and add glucose and castor sugar. DO NOT BOIL.
-Place warmed stones into warm solution and cover the stone with liquid.
-leave on low temperature for 24 hours but DONT BOIL.
-Remove with tweezers and let cool.Use a paper town to wipe away access.
The next steep is to carbonize the sugar in the stone. Place the stones on a metal or pyrex dish and place in a kiln at 500 F degrees for one hour.This will burn or carbonize the sugar in the stone.
_When the stones have cooled clean on a grinding wheel.
Remember to take all precautions with gloves and mask and clothing with good ventilation.
This is a natural product so results may vary a bit due to how porous the sandstone is. Some material will have to be treated a few times to get good results. You can also experiment with various temperatures as i like to cook with lower temperatures.
You may have to treat a stone a few times to get the desired result.
Remember to have fun!
In the learning section of opal actions there is details on how to treat with acid and sugar but this sugar only gets good results if the material is porous

 The surface is porous so its hard to get a good finish.
You can polish as a natural stone or coat it with resin to get a better finish.
We suggest a polymer resin as its stable.inert and nontoxic and dosent yellow..Check out our listings of fairy opal polished in sedaopals.Some of there were polished in china under vacume with a amazing finish.
We have also used mono-compontent thermo set resin,cynoacrylates and 2 parts resin but these can turn yellow over time. ive even heard of nail polished used and hardened under uv lights.

The weight and size is app
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Audit Information

This auction has been audited by a Gemstone Sheriff and they have found the following: View Report
Description Accurate
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Filled Cavities or Fissure/Cobalt listing are no longer accepted on Gem Rock Auctions. Please remove.

Last updated 25th Oct 2021
Requested 25th Oct 2021

Pricing & Details

Bid Increment $1
Starting Bid $1
Auction ID 1633190
Watchers 10 watching
Viewed 253 times
Starts 24th Oct 2021 6:00pm PDT
Ends 21st Nov 2021 5:01pm PST

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Quality Rough Details

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