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 Post subject: 'Onyx'
PostPosted: Sun Jan 17, 2010 11:14 am 
One of the most common materials found in UK High Street men's jewellery is 'Black Onyx'.

I'm aware that generally this material is sugar/acid dyed (a-la opals) with carbon deposition. However is this always the case?

In the back of my mind, I remember Onyx as generally being a white-to-black banded material - although I believe it can occur in other colours.

Can the black-only material be produced by nature, or is it another example of exclusive 'neccessary treatment'?

A friend of mine was quite dissappointed that his knuckle-bitingly over-priced High Street 'onyx' ring was actually probably a grey piece of quartz artificially coloured by carbon, but I ought to make sure this is definitely the case.

In the very depths of Google, I did find a few sources describe natural black-only onyx as 'very rare', but as it's the internet who knows. The general concensus seems, though, to be that such material doesn't exist. If it did, I assume it would be readily identifiable from the carbonised commercial material?


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PostPosted: Sun Jan 17, 2010 1:18 pm 
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Hi Kyriakin,

To my knowlege true onyx was indeed the naturally occuring untreated banded black/brown to white banded material. True untreated black onyx is very rare indeed especially in fairly large sizes.

There are a few natural untreated alternatives that look very similar visually such as black jade, black tourmaline (schorl), black spinel (or jet and black coral which are much softer) to name a few that come to mind.


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PostPosted: Sun Jan 17, 2010 1:51 pm 
I did recommend black spinel at the time, which is found in every shape and size at a certain shop in Kanchanaburi (for those interested, it is not on the main 'bar' road towards the bridge, where most of the tourist junk is, but near to the station).

I imagine the mono-crystalline materials such as schorl and spinel would have a higher lustre, and maybe lack the desired 'matt' finish that the dyed chalcedony would have. Unless, it is possible to recreate this kind of lustre on a crystalline material with a certain type of polishing method?

Black jadeite is a very good call though. I've seen high quality non-green/lavender jadeite pieces sell at very conversative prices.

The problem is the automatic onyx=black preconception in the general public. It stands up there with jade=green, sapphire=blue, opal=white and garnet=red.


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PostPosted: Sun Jan 17, 2010 3:11 pm 
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Black jade is indeed the closest to black onyx visually.


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PostPosted: Sun Jan 17, 2010 5:04 pm 
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lyric wrote:
Hi Kyriakin,

True untreated black onyx is very rare indeed especially in fairly large sizes.

I'll agree with that in general though I have 2 chunks of totally untreated jet-black chalcedony that total 50+ pounds. I could have bought a ton or more if I'd needed it when the site in Namibia was being mined a few years ago. Undyed black chalcedony isn't abundant but I've seen quite a few examples when field collecting.

Here's a Gary Roskin article that discusses the material and nomenclature: http://www.jckonline.com/article/293465-Black_Chalcedony.php

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PostPosted: Sun Jan 17, 2010 5:14 pm 
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the onix you talck is the same who looks like marble?
if you talking about this stuff there are a lot of colors and i saw this selling by the ton on pakistany dealer, but as usual i don´t remember who he is


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PostPosted: Sun Jan 17, 2010 7:28 pm 
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Rom,

For some reason, each time that I needed some material to use for animal carvings, large rings, cuff links parts or bangles, it was always a problem to find undyed black onyx from Idar Oberstein, Paris, Geneva or New York. I usually ended up using black jade as a substitute.
I trust that it is being mined but where does it go?

Lyric


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PostPosted: Sun Jan 17, 2010 9:31 pm 
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Lyric,
I can only account for the material I own. I have no idea where the rest of the production ended up. I just remember that Namibia was the source and assume some probably went to I-O due to the long-standing Namibian "German connection."

I'll try to find my invoice and let you know the name of the company that supplied mine. It was a U.S. company.

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PostPosted: Mon Jan 18, 2010 12:21 am 
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Hi Rick,

Thank you! I would be greatful if you you would please be kind enough to let me know if you can find your supplier's trail.
Are you sure it was not dyed or treated in anyway?

Best,

Lyric


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PostPosted: Sun Feb 14, 2010 2:02 am 
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ROM wrote:
Lyric,
I can only account for the material I own. I have no idea where the rest of the production ended up. I just remember that Namibia was the source and assume some probably went to I-O due to the long-standing Namibian "German connection."
I'll try to find my invoice and let you know the name of the company that supplied mine. It was a U.S. company.


untreated black onyx.... :?:

please ROM do you mind let me know where is the U.S.A company....?
thanks!

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