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 Post subject: The different between Indonesian Opal and Ethiopian Opal
PostPosted: Sat Jun 11, 2011 11:43 am 
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this is my Ethiopian Opal

Image

and this one is Indonesian Opal

Image

can you see the different? many in here (Indonesia) people can't make a decision about the differences between Indonesian opal and Ethiopian opal, it looks like twins.

some people believe indonesian opal has better movement of rainbow rather than ethiopian, and another says ethiopian harder than indonesian.

but i just want ask the gurus what the differences between it?


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 Post subject: Re: The different between Indonesian Opal and Ethiopian Opal
PostPosted: Sat Jun 11, 2011 8:18 pm 
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Hi, we lived in Jakarta when I was a child. My dad is a geologist and had spent time in Broken Hill (lightning ridge)Australia looking for opal. He bought some pieces that were alrady cabbed. They were both clear with great play of color, and also pitch black with play of color. Unfortunately they were all very delicate and broke into pieces as they dried. The blacks were so dry they would stick to your tongue (painfully). Very interestingly the opals had the "distinctive" columnar stucture to the play-of-color (also called finger-like I believe) that is described as unique to Ethiopian.
We wondered at the time (early 1970"s) if there was some sort of stabilization possible. In those days we did not know of it. From what I understood they were dug from wet soils, and didn't survive drying for long. The colors were beautiful. The blacks were not smoked; as the play of color went into the stones. Also, the brown ones would lose all play-of-color when wet, but the fire returned when they dried out; a reverse of usual hydrophane (sp?). Made a small brown one into a pendant for my sister and I believe it is still stable. The formation is most probably similar to the Ethiopien material, from basaltic sources (double check that as I am shooting from the hip here).
Great material, very similar to Ethiopian; I hope both sources prove one day to be stable. Regards, Richard.


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 Post subject: Re: The different between Indonesian Opal and Ethiopian Opal
PostPosted: Sat Jun 11, 2011 8:22 pm 
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Sorry, just want to clarify: My dad was very interested in opal, and did spend time at Lightning Ridge. BUT; the opal I was talking about that he bought already cabbed was Indonesian material. I was not at all talking about Australian material. Okay, that should clear it up a little. Thanks, R.

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 Post subject: Re: The different between Indonesian Opal and Ethiopian Opal
PostPosted: Mon Jun 13, 2011 7:29 am 
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Richard wrote:
Sorry, just want to clarify: My dad was very interested in opal, and did spend time at Lightning Ridge. BUT; the opal I was talking about that he bought already cabbed was Indonesian material. I was not at all talking about Australian material. Okay, that should clear it up a little. Thanks, R.



okay let's clarify which one is better, i think both of them has beautiful rainbow color well it's just my tought. i hate to say but indonesian people always to say that indonesian opal is the best rather than any kind of opal. when i gave them a few of my ethiopian collection then i said "it's indonesian" they believed about that, in my opinion ethiopian is more solid due to i put it straight above the light, it's not getting crack different with indonesian opal especially indonesian black opal, so how to explain the common different between both of it?

thanks

D


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 Post subject: Re: The different between Indonesian Opal and Ethiopian Opal
PostPosted: Mon Jun 13, 2011 10:42 am 
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Just as a further clarification ( :D ) there is nothing diagnostic about the appearance of either of those opals which would determine where the opal was mined.
They could just as easily all be from Mexico.....or all from Ethiopia....or.....


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 Post subject: Re: The different between Indonesian Opal and Ethiopian Opal
PostPosted: Thu Jan 07, 2016 8:42 pm 
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I saw in youtube... Indonesian opal nearly all are heavily smoked, heated and oiled especially for the black type. If I want to buy Indonesian opal, I choose Wonogiri fire opal and Banten crystal/white opal...


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 Post subject: Re: The different between Indonesian Opal and Ethiopian Opal
PostPosted: Sun Mar 12, 2017 12:55 pm 
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Hi all, I am from Indonesian and happen to be a collector and also seller of Indonesian Opal.

The main different of Indonesian and Ethiopian opal is its respons when immerse them in water.

Ethiopian opal will loose its play of colors after soaking it in water for some period of time (1 to 24 hours). But don't worry, the play of colors will back after some period of time (several day or several weeks) when the stone gradually loose its excess water.

Indonesian opal has no problem with water. You may immerse it in water for months and the play of colors still there. infact, the color become more vivid because it is loosing any tiny dirty particles still trap inside.

As of this writing, you can still find natural (black) opal from Indonesia, mostly small ones. The big ones quite rare and priced between US$ 100-300 per carat depend on the play of colors pattern. Reputable seller usually provides gemlab memo/certificate along the stone.

When you are in doubt about the origin of the opal (Ethiopian/Indonesian), just ask the seller permission to immerse it in water. Cool/warm water will give immediate result (15-30 minutes.)

I own both of Ethiopian and Indonesian opal, and in term of rigidness, my opinion is about the same. Just make sure you don't wear Ethiopian opal in cool or high humidity environment or get it intouch with water too much.


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 Post subject: Re: The different between Indonesian Opal and Ethiopian Opal
PostPosted: Sun Mar 12, 2017 1:01 pm 
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Iskandarman wrote:
I saw in youtube... Indonesian opal nearly all are heavily smoked, heated and oiled especially for the black type. If I want to buy Indonesian opal, I choose Wonogiri fire opal and Banten crystal/white opal...


I believe you are talking about petrified wood which in Indonesia is commonly called black opal or sempur.

The real opal cannot be heated or it will crack.

For safety, always ask for gemlab memo/certificate when buying an opal. Especially with the expensive ones.


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 Post subject: Re: The different between Indonesian Opal and Ethiopian Opal
PostPosted: Mon Mar 13, 2017 4:57 pm 
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Hello,

KC.SHiN: wrote:
Indonesian opal has no problem with water. You may immerse it in water for months and the play of colors still there. infact, the color become more vivid because it is loosing any tiny dirty particles still trap inside."

That is not my experience. When ,now 25years back, one Indonesian Friend of mine brought some Indonesian Opals (iirc they were from Java) for cutting i first got quite shocked when they turned to opaque grey pieces of Stone with no colourplay left when they became wet at the cutting wheel.After completing the Cabochons we left them in the Sun to dry out which brought back the play of colour.Not all of the Stones showed that reaction,there were Crystal-Type Opals that behaved "normal" during wet-cutting.The darker and just slightly translucent ones turned opaque when immersed in Water.No ideas as to why that is.With Ethiopian Stones ,which i cut since ca.7/8 years, there is often the reaction of turning crystalclear when wet and coming back to normal after drying though there are many stable/not Hydrophane Stones,depending on the source.
And to your Indonesian friends saying Indonesian Opals are the best:never mind as also the Aussie Opals are the best as well as the Brasilian ones,not to speak of the Mexican Stones :-" :-"
best wishes
Gemse


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 Post subject: Re: The different between Indonesian Opal and Ethiopian Opal
PostPosted: Tue Mar 14, 2017 12:32 am 
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Clearly the stones from Spencer, Idaho are the best :lol:

I purchased one Indonesian stone on facebook, one of the wood opals. When it came it was jet black with spots of fire, very similar in appearance to a smoked Welo opal. But it also felt very oily, so I decided to stick it in acetone for a bit. It came out lighter brown, porous with wood grain and a rough surface, no fire visible at all. Very cool material, and the price was right for what it was. I have seen a lot of this kind of stuff offered for sale with no treatment disclosure, and it has definitely dampened my interest in trying more Indonesian opal out, especially when I can get high quality Ethiopian rough fairly inexpensively right now.


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 Post subject: Re: The different between Indonesian Opal and Ethiopian Opal
PostPosted: Wed Mar 22, 2017 9:26 am 
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99.9% of all Indonesian Opal sold as such, is Welo Opal, whether smoked, or not. Don't be fooled. :^o

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Thank you...Thank you very much... Richard.


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