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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Sun Jul 15, 2018 1:11 am 
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Differences with glass:
1:The stones are doubly reflective, exam the inclusions by microscope with out polarizer filter,the image will be doubled. (picture 1)
2:They are harder than glass.
3:They have liquid inclusions with bubbles which you can not find in glass. (picture 2)


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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Sun Jul 15, 2018 1:14 am 
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Differences with lab-grown quartz:
1:They have multiple types of inclusions, including the typical inclusions in natural quartz. (picture 3)
2:The stones have cavities and fissures. Most of the cavities were sealed by glue before the cutting and polishing process, but I can still find some chambers in the stones with small openings.(not something that can be grown in lab) (picture 4)
3:Some specimens have those so-called "phantom" inclusions , also a sign of natural quartz. (picture 5)


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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Sun Jul 15, 2018 1:17 am 
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Differences with imitations of rutiled quartz:
1:The inclusions in the specimens are gold threads , not foils. The gold threads are extremely fine , they are about 20μm in diameter, less than 1/3 of the diameter of human hair, and they have pointed tips inside the stone(no sign of cutting). (picture 6)
2:Though the specimens have glue in the cavities and fissures, the gold threads are surrounded by quartz, not glue or epoxy,and they are not just in a layer between two pieces of quartz. They grew all the way on to the surface of the polished stones. This has proved by the SEM-EDS analysis results.(the Au in the result is from the gold coating. No element of glue or epoxy detected near the exposed tips of the gold threads on the surface of the stone) (picture 7,picture 8 )
3:All the specimens are not mounted, the imitations are all mounted with metal because they need to hide the obvious layer of epoxy.
4:Filiform gold does exist in nature(just very rare) while linear gold foil does not. I copied this text from mindat:
Morphology (Gold):
Usually crude to rounded octahedra, cubes, and dodecahedra to 2 cm. Often elongated along [100] or [111] directions, forming herringbone and dendritic twins. Flattened {111} plates with triangular octahedral faces. Rarely as wires ([111] elongation); reticulated; dendritic; arborescent; filiform; spongy; also massive in rounded fragments, flattened grains and scales (gold dust).

Finally, though I still unable to establish contact with GIA(HongKong), I can find some other institution to identity the stone first , if they think the stone is natural , they will give me a certificate. It might not good enough ,but I think it can more or less prove something.


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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Sun Jul 15, 2018 1:47 am 
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It might be worth sending a message to Nathan Renfro (with the GIA in Carlsbad, Ca). He's a serious gem inclusion badass.

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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Sun Jul 15, 2018 2:05 am 
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Stephen Challener wrote:
It might be worth sending a message to Nathan Renfro (with the GIA in Carlsbad, Ca). He's a serious gem inclusion badass.

Actually, he is the one who suggested me to contact GIA HongKong.
But since the IP address from mainland of China is blocked by GIA server( Email too), I still unable to contact them, but i'll keep trying.


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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Sun Jul 15, 2018 12:46 pm 
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so far i don't see anything definitive to point it out as natural!
your polariscope test is not enough, have you done RI? even if it is quartz again assembled quartz as Barbra said is another possibility

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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Sun Jul 15, 2018 1:26 pm 
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roshanravan wrote:
so far i don't see anything definitive to point it out as natural!
your polariscope test is not enough, have you done RI? even if it is quartz again assembled quartz as Barbra said is another possibility

I can't do those tests by myself , but I can find a Inspection Center to do the regular tests and I will, I tell you the results when it is done.
There is glue in those specimens ,but only to fill the cavities and fissures so to protect the stones from cracking apart during the cutting and polishing process. If the quartz were assembled together with epoxy and the inclusions were put in the layer of epoxy artificially , the SEM-EDS analysis can definitely detect element of epoxy near the exposed spots of the inclusions, but it didn't.


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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Sun Jul 15, 2018 2:13 pm 
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I just tested my specimen on the Raman.
I've been foiled.
The "quartz" is glass.

I did a little looking around and zbhjzm is correct. A lot of this material is being represented as rutilated quartz on Etsy

I should have gone with a cup of afternoon coffee instead of my pendant.


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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Sun Jul 15, 2018 8:17 pm 
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Barbra Voltaire wrote:
I just tested my specimen on the Raman.
I've been foiled.
The "quartz" is glass.

I did a little looking around and zbhjzm is correct. A lot of this material is being represented as rutilated quartz on Etsy

I should have gone with a cup of afternoon coffee instead of my pendant.



hahaha, don't worry it happens to all of us but it's small price to pay to get the experience, as you know Quartz is very tricky and there is no easy way even for advanced instruments to identify synthetic Quartz.

zbhjzm wrote:
roshanravan wrote:
so far i don't see anything definitive to point it out as natural!
your polariscope test is not enough, have you done RI? even if it is quartz again assembled quartz as Barbra said is another possibility

I can't do those tests by myself , but I can find a Inspection Center to do the regular tests and I will, I tell you the results when it is done.
There is glue in those specimens ,but only to fill the cavities and fissures so to protect the stones from cracking apart during the cutting and polishing process. If the quartz were assembled together with epoxy and the inclusions were put in the layer of epoxy artificially , the SEM-EDS analysis can definitely detect element of epoxy near the exposed spots of the inclusions, but it didn't.

i speak from experience don't rely on X-ray spectroscopy (SEM-EDS, EDX, EDXS or XEDS) for gemology purposes at all, it is giving misleading results, except in precious metals and pearls X-ray spectroscopy has almost no use in advanced gemology.
i have seen many people saying they have find a stone and got X-ray spectroscopy report from university or else... the Energy-dispersive X-ray spectroscopy instruments should not use this way, unless your specimen is powder or metal surface the X-ray spectroscopy is not helpful, it is useful in Identifying Cuprian Tourmalines, some use in pearl identification also CZ’s show up on XRF because of the Zirconium metal.

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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Sun Jul 15, 2018 11:58 pm 
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roshanravan wrote:
Barbra Voltaire wrote:
I just tested my specimen on the Raman.
I've been foiled.
The "quartz" is glass.

I did a little looking around and zbhjzm is correct. A lot of this material is being represented as rutilated quartz on Etsy

I should have gone with a cup of afternoon coffee instead of my pendant.



hahaha, don't worry it happens to all of us but it's small price to pay to get the experience, as you know Quartz is very tricky and there is no easy way even for advanced instruments to identify synthetic Quartz.

zbhjzm wrote:
roshanravan wrote:
so far i don't see anything definitive to point it out as natural!
your polariscope test is not enough, have you done RI? even if it is quartz again assembled quartz as Barbra said is another possibility

I can't do those tests by myself , but I can find a Inspection Center to do the regular tests and I will, I tell you the results when it is done.
There is glue in those specimens ,but only to fill the cavities and fissures so to protect the stones from cracking apart during the cutting and polishing process. If the quartz were assembled together with epoxy and the inclusions were put in the layer of epoxy artificially , the SEM-EDS analysis can definitely detect element of epoxy near the exposed spots of the inclusions, but it didn't.

i speak from experience don't rely on X-ray spectroscopy (SEM-EDS, EDX, EDXS or XEDS) for gemology purposes at all, it is giving misleading results, except in precious metals and pearls X-ray spectroscopy has almost no use in advanced gemology.
i have seen many people saying they have find a stone and got X-ray spectroscopy report from university or else... the Energy-dispersive X-ray spectroscopy instruments should not use this way, unless your specimen is powder or metal surface the X-ray spectroscopy is not helpful, it is useful in Identifying Cuprian Tourmalines, some use in pearl identification also CZ’s show up on XRF because of the Zirconium metal.

Yes, the SEM-EDS analysis can not tell if the stone is natural quartz, but it is the only way to identify the inclusions as gold without damage the stone. So, I'll find an Inspection Center to identify if it is quartz.


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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Mon Jul 16, 2018 12:06 am 
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Barbra Voltaire wrote:
I just tested my specimen on the Raman.
I've been foiled.
The "quartz" is glass.

I did a little looking around and zbhjzm is correct. A lot of this material is being represented as rutilated quartz on Etsy

I should have gone with a cup of afternoon coffee instead of my pendant.

That is why they are so cheap....


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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Mon Jul 16, 2018 7:27 am 
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zbhjzm wrote:
Yes, the SEM-EDS analysis can not tell if the stone is natural quartz, but it is the only way to identify the inclusions as gold without damage the stone. So, I'll find an Inspection Center to identify if it is quartz.


my friend this is why i am trying to explain, the X-ray spectroscopy is not useful here unless the metal (in this case Gold) is part of the chemical formula, like Identifying Paraiba tourmaline due to the presence of copper (Cu) and manganese (Mn) in chemical formula, in order for you to get more conclusive result you should use destructive test, like testing powder specimen which needs proper sampling.

also regarding the shape of the gold inclusion in your photos, it's been years since i have studied Inclusions and mostly we pay attention to those in Ruby, Sapphire, Emeralds to identify the origin the rest is not very practical in jewelry business, so my knowledge might be little bit rusty! but something is bothering me! specially the wire shape of the inclusions. you know gemologist are like detectives they have to check all the facts.
Natural Quartz is crystallizes in a hydrothermal environment and ore minerals like gold, silver and copper can be present and become part of the inclusions but the thing is in that environment having a tube/wire shape or as i have seen in one of your pictures flat Wire silver is highly unlikely! specially considering the temperature of the hydrothermal veins also you do not find gold or silver in nature like those wire shapes.

anyway disregard you X-ray spectroscopy results you do not get to the truth this way

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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Mon Jul 16, 2018 9:49 am 
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roshanravan wrote:
zbhjzm wrote:
Yes, the SEM-EDS analysis can not tell if the stone is natural quartz, but it is the only way to identify the inclusions as gold without damage the stone. So, I'll find an Inspection Center to identify if it is quartz.


my friend this is why i am trying to explain, the X-ray spectroscopy is not useful here unless the metal (in this case Gold) is part of the chemical formula, like Identifying Paraiba tourmaline due to the presence of copper (Cu) and manganese (Mn) in chemical formula, in order for you to get more conclusive result you should use destructive test, like testing powder specimen which needs proper sampling.

also regarding the shape of the gold inclusion in your photos, it's been years since i have studied Inclusions and mostly we pay attention to those in Ruby, Sapphire, Emeralds to identify the origin the rest is not very practical in jewelry business, so my knowledge might be little bit rusty! but something is bothering me! specially the wire shape of the inclusions. you know gemologist are like detectives they have to check all the facts.
Natural Quartz is crystallizes in a hydrothermal environment and ore minerals like gold, silver and copper can be present and become part of the inclusions but the thing is in that environment having a tube/wire shape or as i have seen in one of your pictures flat Wire silver is highly unlikely! specially considering the temperature of the hydrothermal veins also you do not find gold or silver in nature like those wire shapes.

anyway disregard you X-ray spectroscopy results you do not get to the truth this way

Actually ,someone suggested me to do the SEM-EDS analysis.

https://www.mineral-forum.com/message-b ... c&start=20
This is how the analysis was performed:
The inclusions have exposed tips on the surface of the stone, that makes the identification of the inclusions through SEM-EDS analysis possible. I marked the exposed spot out with Scotch tape (picture 1). The operator then found the spot under electron microscope and performed the analysis(picture 2), the result confirmed that the inclusions are gold(picture 3).

I know there are some misunderstandings here. The SEM-EDS analysis result I posted in the previous reply is on the quartz itself. The Au in that result is from the gold coating ,not the inclusions. I didn't take that result as the proof of the inclusions are gold....


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Last edited by zbhjzm on Mon Jul 16, 2018 10:20 am, edited 3 times in total.
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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Mon Jul 16, 2018 10:04 am 
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roshanravan wrote:
zbhjzm wrote:
Yes, the SEM-EDS analysis can not tell if the stone is natural quartz, but it is the only way to identify the inclusions as gold without damage the stone. So, I'll find an Inspection Center to identify if it is quartz.


my friend this is why i am trying to explain, the X-ray spectroscopy is not useful here unless the metal (in this case Gold) is part of the chemical formula, like Identifying Paraiba tourmaline due to the presence of copper (Cu) and manganese (Mn) in chemical formula, in order for you to get more conclusive result you should use destructive test, like testing powder specimen which needs proper sampling.

also regarding the shape of the gold inclusion in your photos, it's been years since i have studied Inclusions and mostly we pay attention to those in Ruby, Sapphire, Emeralds to identify the origin the rest is not very practical in jewelry business, so my knowledge might be little bit rusty! but something is bothering me! specially the wire shape of the inclusions. you know gemologist are like detectives they have to check all the facts.
Natural Quartz is crystallizes in a hydrothermal environment and ore minerals like gold, silver and copper can be present and become part of the inclusions but the thing is in that environment having a tube/wire shape or as i have seen in one of your pictures flat Wire silver is highly unlikely! specially considering the temperature of the hydrothermal veins also you do not find gold or silver in nature like those wire shapes.

anyway disregard you X-ray spectroscopy results you do not get to the truth this way

I don't know why the Gold wires are in the stones, maybe that is something worth studying.
The "flat Wire silver" is actually Cannizzarite, this also confirmed by the SEM-EDS analysis.(picture 1, 2). As you can see from the result , S Pb and Bi are the elements of Cannizzarite, Sb is impurity and the Au is from gold coating.
Cannizzarite is a rare mineral , it might look like flat Wire silver ,but it is natural.(picture 3)
https://zh.mindat.org/min-883.html


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 Post subject: Re: Hairlike Gold inclusions in Quartz??
PostPosted: Mon Jul 16, 2018 10:39 am 
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Filiform gold does exist in nature as described on mindat and I even found a picture of gold wire in quartz:
https://uwaterloo.ca/wat-on-earth/news/ ... production


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