diamond getting black carbon inside stone after 6 month

[talthoff]

Ok, I bought a high quality diamond ring an in July of 2002. It is a .733ct marquee diamond that was free of any defects by the naked eye. Recently, in the last few months the stone has developed some black spots. One is a rather large spot; the other is small but is kinda like a string shaped in a curly-Q.

I spoke with the owner that said that diamond don''t get defects over time. He said that it was from dirt, soap, ect. Getting behind it and that shows the internal markings more. He stated that after a steam cleaning at the store it doesn''t show the defects as much. I have not scene this so I can''t confirm since it''s at the store still. He also said that the outside of the ring looked to be perfect, not damaged from getting knocked around.

The other thing that concerns me is that I don''t have any paperwork for the diamond. The only thing that the store gave me was the receipt that says that it''s a .733 ct marquee diamond. Is it required that I get some paperwork?

Any help would be greatly appreciated.

Tim Althoff

 

[DiamondOptics]

Hi talthoff,


Do you know what the clarity of your diamond is?

Try not to jump into any conclusions until
you can varify exactly what the problem is...

For the diamond to spontaniously form some type
of anomaly may be the result of damage, among other things.

My advise would be to have your diamond examined
by an expert like the Rock Doc, or some others
found in the pricescope directory.

Kirk Konst

 

[pyramid]

My sister has a diamond which when clean has a small black carbon spot which you can hardly see or would not unless you know it is there. However when her stone has not been cleaned for a while the black spot becomes more apparent. She recently had it cleaned and I looked for the spot but could not see it again until I had looked for about 3 minutes.

Maybe it is something like this

 

[niceice]

The situation that Pyramid describes is quite common, as diamonds become dirty / grimy the inclusions often become more visible.

 

[GeoGeoUWP]

The real question is where the black on the diamond is. Is it on it or in it? As a student of geology in know that diamonds are relatively unstable at the surface. They are a very high temp and high pressure form of pure carbon that doesn't like to be at the surface at all. The other question is how long the diamond that you bought has been at the surface. Depending on the age of the diamond it can actually start to change into one of the other common forms of pure carbon that is used by society, graphite. Over time a diamond will change into graphite because of the instability of diamond at surface temp and pressure. The only thing is the abruptness of the black marks appearing on/in the diamond. That's all I can think of from your description of the problem.

 

[Kaleigh]

Geo,
This thread is 2 years old.

 

[JulieN]

Just because I don''t want misinformation floating around...

Yes, graphite is thermodynamically preferred over diamond. The C-C bonds are lower in energy and are therefore more stable. However, the activation energy for diamond -->graphite is sufficiently high that diamond will not spontaneously turn into graphite.

 

[kenny]

Wow.
I'm going to check to see if any of the graphite in my pencil leads has turned into diamonds.

 

[oldminer]

"I'm going to check to see if any of the graphite in my pencil leads has turned into diamonds."

Only if you squeeze the pencil very tightly for about 50 million years.... Be patient!

BTW, how did this thread get resurrected?

 

[Roughdealer]

Geo:

I heared about Companies like GE and Wstinghouse, some in Israel had sucessfully turn into diamonds a piece of Carbon ( of course Diamond are a Carbon piece) trough HPHT ( High pressures high temperatures ) treatments which try to repro the natural process , pls explain me more about the inverse process.....I want know more details about this profitable business.

When i studied ABOUT DIAMONDS in south africa I HEARED SOMETHING ABOUT A VERY TOP SECRET PROCESS ( NOT POLISHING OR CUT , PLS..!!) THAT DE BEERS HAVE , THAT ALLOW TROW OFF THE SMALLEST CARBON PARTICLES FROM THE ROUGH IF THEY ARE RELATIVELY CLOSE OF THE SURFACE . MAYBE THEY USE SOMETHING ABOUT THE BIZARRE FACT YO ARE TALKING TO.....BUT THIS IS A ROUGH DIAMOND URBAN LEGEND OR SO... EVERYBODY TALK ABOUT IT BUT REALLY NOBODY HAS DONE IT BY HER/HIMSELF...

 

[Garry H (Cut Nut)]

Date: 11/1/2005 11:22:02 PM
Author: GeoGeoUWP
The real question is where the black on the diamond is. Is it on it or in it? As a student of geology in know that diamonds are relatively unstable at the surface. They are a very high temp and high pressure form of pure carbon that doesn''t like to be at the surface at all. The other question is how long the diamond that you bought has been at the surface. Depending on the age of the diamond it can actually start to change into one of the other common forms of pure carbon that is used by society, graphite. Over time a diamond will change into graphite because of the instability of diamond at surface temp and pressure. The only thing is the abruptness of the black marks appearing on/in the diamond. That''s all I can think of from your description of the problem.
-Alex Ketchpaw

Dear GEO,
Did anyone ever tell you a little bit of knowledge can be very dangerous?

Yes diamonds are unstable out side the High Pressure High temp zones where they grew at around 200km or deeper below the earths surface when the earth was younger an hotter. But when they get to the earths surface they are kind of snap frozen and will be quite stabe for billions of years.
The only risk is if you get them very hot and under extreme pressure (HPHT) , they could revert (dissolve) back into free carbod or lower structural levels, like graphite.

Diamonds must come from their deep stable HPHT zones to the surface very very quickly - or else they do resovle and graphitize - that means a very violent volcanic eruptions where they travel at speeds of up to 100 miles or kilometers per hour from depths to the earth surface.

No one needs worry they will disolve or turn to graphite at room temperature - or even where i am at present - the top end of very tropical Australia.