CIBJO releases Gemmological Special Report: considers process of separating measurable facts from opinion; See Gemological Articles below.
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 Post subject: Black Diamond ?
PostPosted: Wed Nov 23, 2011 10:36 pm 
Just have one simple question - What is Black Diamond exactly ? :)


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 Post subject: Re: Black Diamond ?
PostPosted: Wed Nov 23, 2011 10:46 pm 
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If it's a natural diamond, it is one with numerous black inclusions lining its cleavages and fractures. There will be some colorless areas within the structure.

If it's an irradiated diamond, it will actually be a dark blue or dark green throughout with no colorless areas inside.

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 Post subject: Re: Black Diamond ?
PostPosted: Wed Nov 23, 2011 11:41 pm 
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Perhaps this old thread will shed some light.


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 Post subject: Re: Black Diamond ?
PostPosted: Thu Nov 24, 2011 12:09 am 
Thank you ladies, I read it and understood quite a bit. But tell me this, if a diamond is consist of more than 50% graphite can it still be called a diamond ?
Someone please shed some light in what cases a diamond could be called a natural black diamond ? ](*,)


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 Post subject: Re: Black Diamond ?
PostPosted: Thu Nov 24, 2011 12:36 am 
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Quote:
if a diamond is consist of more than 50% graphite can it still be called a diamond


Didn't you answer the question with the question? If a diamond contains.....it's a diamond.

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Someone please shed some light in what cases a diamond could be called a natural black diamond ?

I would define it as an untreated diamond which appears black.....like the Black Orloff


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 Post subject: Re: Black Diamond ?
PostPosted: Thu Nov 24, 2011 1:50 pm 
Alrighty, thank you :)
This one has a GIA certificate as a natural black diamond - http://www.langerman-diamonds.com/shop/ ... ed_Diamond
But I can't see any transparent area :/


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 Post subject: Re: Black Diamond ?
PostPosted: Thu Nov 24, 2011 2:22 pm 
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Ask them about it.
Perhaps they have a magnified shot they can send you.


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 Post subject: Re: Black Diamond ?
PostPosted: Wed Dec 07, 2011 1:57 am 
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Natural diamonds which has black color it's called black diamonds.


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 Post subject: Re: Black Diamond ?
PostPosted: Wed Dec 07, 2011 11:44 am 
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diamondzul-diamonds wrote:
Natural diamonds which has black color it's called black diamonds.

Thank you for your response, a little simplistic, but I guess that rather sums it up.


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 Post subject: Re: Black Diamond ?
PostPosted: Wed Dec 07, 2011 4:20 pm 
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this being said, I think one should make the difference between a black diamond of polycrystalline structure, and a black diamond of monocrystalline structure.


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 Post subject: Re: Black Diamond ?
PostPosted: Wed Dec 07, 2011 5:22 pm 
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That is right, the polycrystalline (Carbonado) is pretty different as it is not only hard, it is also tough. Like difference between rock crystal and chalcedony.

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 Post subject: Re: Black Diamond ?
PostPosted: Thu Dec 08, 2011 8:09 pm 
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boart (bort) is polycrystalline and can also be black, just like carbonado.

note that there's quite some confusion about the term 'boart' because some people use it to refer to any low quality diamond (polycrystalline or monocrystalline) while this term should only be used in reference to a polycristalline variety of diamond.
There are three polycrystalline varieties of diamond: carbonado, boart, and ballas, all three are polycrystalline but their structure is different one from another.


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 Post subject: Re: Black Diamond ?
PostPosted: Mon Dec 19, 2011 5:40 pm 
Hmm... so a diamond can have different structures, thats interesting... :D


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 Post subject: Re: Black Diamond ?
PostPosted: Fri Dec 30, 2011 5:33 am 
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Black Diamonds are real genuine diamonds.They come out of the earth as Diamonds that don't look exactly black. It has enhanced and after that it become black diamonds.


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 Post subject: Re: Black Diamond ?
PostPosted: Fri Dec 30, 2011 11:24 am 
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There are naturally occurring, untreated blacks, like the Black Orlov.
Read this thread for a little clarification Jamesdiamonds:
viewtopic.php?f=7&t=13301


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