Green diamonds?

[Jaylyn]

I met a woman that had a green diamond set in a ring. The stone was a very light green with an iridescent quality. It looked almost like a mystic gemstone, and I was suprised to find out that it was a diamond. I've searched the net and have not come across a stone that looks like hers. She said that she bought it at an estate auction, but I did not ask her how much she paid for it. I was wondering if anyone might know where I could find info on a diamond like the one described, and how they compare in price to other diamonds.

 

[pricescope]

Green Diamonds
Green diamonds have comes in contact with radioactive minerals such as uranium. Radiation stains the outside of the diamond, so the cutter must be careful not to cut away too much of the green "skin". Authenticating that the radiation occurred naturally requires laboratory analysis at a leading gemmological institute. Buyer beware!

[/u]

 

[Richard Sherwood]

Natural green diamonds are very rare, very expensive.

Most green diamonds you see are irradiated by man. They are reasonably priced. The formula you hear touted a lot is that they are priced according to an "M" color, with a premium added for the cost of treatment. I would say that's basically correct, but there is still the same subjectivity to their pricing that you find in natural fancy colored diamonds, in that if it's a particularly beautiful green it will command quite a bit more than an average green.

I've not run across any HPHT lab created (synthetic) green diamonds, although I've seen several green tinted fancy yellows. I think that the green color is less common in both the HPHT treated naturals and the HPHT lab created stones. I'll do some research on it.

That "tint" information is interesting, Furthermore. I hadn't heard it before. I have noticed a very light brown tint to a lot of South American stones, some Russian stones with a very light blue tint, and many South African stones with a very light yellow tint. That's where the trade term "cape" originated, by the way, from the trade ships carrying yellow tinted South African stones around the Cape of Good Hope on their journey to Europe.

 

[DiamondExpert]

The "iridescent" quality you refer to may, at least in part, be due to a very strong yellow, green or yellow-green fluorescence of this stone.

 

[mike04456]

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On 6/17/2003 10:27:55 AM Furthermore wrote:

Now, so much with the preamble - I hear that GIA have only ever certified 24 rocks as being real red diamonds and that only 10 of those were of a decent fighting size. Can anyone shed any light on them figures ????
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GIA published a study of pink/red diamonds last summer. They listed 15 reds they've graded ranging from 0.25 to 5.11 ct, though the list also says "Not all red diamonds listed due to client confidentiality." So who knows?

Any well-saturated green/yellow-green/blue-green diamond should be considered treated until proven otherwise, as these colors are extremely rare in nature. Anyone who has one for sale will have oodles of certs proving natural color, and the truth is that unless you play baccarat regularly in Monaco, you're not the sort of person who will ever see one anyway. So consider 'em all treated.

Oh, and the "estate piece" element means nothing--diamond color alteration by irradiation has been known since the early 20th century.

 

[Richard Sherwood]

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diamond color alteration by irradiation has been
known since the early 20th century.
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We probably should revise that to "since 1950".

They had to be able to split the atom first (mid 40's), in order to come up with those fast neutrons that irradiate the diamonds.

 

[mike04456]

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On 6/17/2003 3:40

4 PM Richard Sherwood wrote:
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diamond color alteration by irradiation has been
known since the early 20th century.
-----------

We probably should revise that to "since 1950".

They had to be able to split the atom first (mid 40's), in order to come up with those fast neutrons that irradiate the diamonds.
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Not quite--early diamond irradiation was performed using radium, which was discovered in 1898.

 

[Richard Sherwood]

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Not quite--early diamond irradiation was performed
using radium, which was discovered in 1898.
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Thanks LawGem. Interesting. I haven't run across any radium irradiated stones. Do you know if it was pretty much isolated experimental instances, or was there a production of any significance?

 

[Heyjud]

Sorry, I can't resist this one.....but
As Kermit said "It's not easy being green" !!!!

 

[mdx]

Green diamonds are often associated with low temperature natural irradiation; These diamonds will usually turn brown if heated to 600 degrees
Some interesting samples originated from the Bingara and Copeton diamond fields of NSW Australia, In particular a bluish green tone. When viewed under a microscope they look like a series of green dots,

Also of interest is the occurrence of rough diamonds with a thick green skin that occur in Ghana and the Central African Republic. These diamonds after polishing produce either a very white (D-E ) or a terrible diesel silver brown. The skin is usually so thick you cant see into the stone making pricing rather tricky.
I have also seen this tinting effect that Furthermore talks about in stones mined by informal miners on the old De Beers “Williamson ”mine in Tanzania. It’s actually pretty common there but the tint is only on the surface. These stone always polish exceptional white seldom retaining the tint.

I think the diamond that Jaytyn may be speaking about is a Chameleon. These diamond change from greenish to yellowish.
Jaytyn does it look like the picture ( This is a 1.27 Oval GIA certed )

Wayne
Melbourne Diamond Exchange ltd

 

[mike04456]

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On 6/17/2003 7:50:28 PM Richard Sherwood wrote:
Thanks LawGem. Interesting. I haven't run across any radium irradiated stones. Do you know if it was pretty much isolated experimental instances, or was there a production of any significance?
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I believe the first attempt was in 1904, and there was indeed a certain amount of commercial production. That came to a screeching halt when it was discovered that radium-treated diamonds were themselves radioactive. You don't see them on the market nowadays because most of those stones are still radioactive.

It would be a while before safer methods were developed.

 

[mike04456]

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On 6/18/2003 11:51:54 AM Furthermore wrote:
Presumably your diamond goes back to white after 4 days - great Bunko booth trick - yet to see a Sierra Leonean scammer try that one, yet. )))))))))) It`d make a novel change from the usual parcel switching, anyway. ))

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I was in the process of correcting this when I saw your follow-up post. Yes, it is indeed permanent.

I wouldn't mess around with radium. It's highly toxic and has been linked with all sorts of cancers because it can replace calcium in your body.

 

[mike04456]

Oh, not to worry--we colonials understand more "UK ironic humour" than you think, we just pretend to ignore it because doing so gets such a rise out of you guys.

There are ways to detect irradiated diamonds, though they are not fool proof. One way is indeed odd patches of color around the culet or elsewhere.

I'd check with GIA on the cyclotron. But I'd heard that reactor time down in Brazil was on the cheap, or else how do they pump out so much of that blue topaz?

 

[Fisheggs]

I recently purchased a Green Diamond ring at an auction. When my husband and I took it to the GIA. the test came back undetermined. They could not tell if the diamond was treated or not. The stone went through 4 weeks of tests and nothing. All I know was the ring was made in 1975 for the woman who's estate we bought this from. Does anyone know anwhere else I could take this ring to to get an answer? The problem is that my insurance company will not insure it because the appriaser said that the ring (being undetermined) then it could appraise for $25,000 based on the report. But The insurance company need conclusive proof over $15,000.

 

[adillus]

Icestore.com sells loose green diamonds.

 

[caj]

I have a green diamond. It is 1/2 karat, and mint green and beautiful. I also have several blue ones. They are irradiated to get the colors, and can be a variety of shades of color depending on the stone itself, and how long it has been treated. The color does not come off because it is all the way "through" the stone, unlike a treated "mystic topaz". I have seen lilacs, deep yellow, pinks, blues, teals, etc. Ask your local jeweler, they can get them in for you to view and choose from. I have a favorite jeweler that calls me everytime he finds something nice and green for me. If I decide not to get it, he just sends it back to his sales rep.

 

[RockDoc]

Hey Richard, you saw my chameleon when it was green...

I got a treated green too, that initially GIA graded as natural.

I knew is was treated cause I had the treatment done. Getting them to change the cert to treated was difficult.

They thought I was truly nuts.

I still have the stone too. Next time i see you I''ll bring it with.

I have some small fancy color ones to we can play with. Red/ Green / Orange/ Violet/ Silver and add them to the SAS database.

Rockdoc