Posted on 05/16/2005 3:19:04 PM PDT by STARWISE
Crystal-clear material is better for optics, scientific applications
May 16, 2005
Researchers at the Carnegie Institution of Washington, D.C. have produced 10-carat, half-inch thick single-crystal diamonds at rapid growth rates (100 micrometers per hour) using a chemical vapor deposition (CVD) process. The size is approximately five times that of commercially available diamonds produced by the standard high-pressure/high-temperature (HPHT) method and other CVD techniques.
In addition, the team has made colorless single-crystal diamonds, transparent from the ultraviolet to infrared wavelengths with their CVD process.
Most HPHT synthetic diamond is yellow and most CVD diamond is brown, limiting their optical applications. Colorless diamonds are costly to produce and so far those reported are small. This limits general applications of these diamonds as gems, in optics, and in scientific research.
Last year, the Carnegie researchers found that HPHT annealing enhances not only the optical properties of some CVD diamond, but also the hardness. Using new techniques, the Carnegie scientists have now produced transparent diamond using a CVD method without HPHT annealing.
"High-quality crystals more than three carats are very difficult to produce using the conventional approach," said scientist Russell Hemley, who leads the diamond effort at Carnegie. "Several groups have begun to grow diamond single crystals by CVD, but large, colorless, and flawless ones remain a challenge. Our fabrication of 10-carat, half-inch, CVD diamonds is a major breakthrough."
The results were reported at the 10th International Conference on New Diamond Science and Technology, Tsukuba, Japan, on May 12, 2005, and will be reported at the Applied Diamond Congress in Argonne, Ill., May 18, 2005.
"The rapid synthesis of large, single-crystal diamond is a remarkable scientific achievement, and has implications for a wide range of scientific and commercial applications," said David Lambert, program director in the National Science Foundation (NSF)'s earth sciences division, which funded the research.
To further increase the size of the crystals, the Carnegie researchers grew gem-quality diamonds sequentially on the six faces of a substrate diamond plate with the CVD process. By this method, three-dimensional growth of colorless single-crystal diamond in the inch-range is achievable.
Finally, new shapes have been fabricated with the blocks of the CVD single crystals.
The standard growth rate is 100 micrometers per hour for the Carnegie process, but growth rates in excess of 300 micrometers per hour have been reached, and 1 millimeter per hour may be possible. With the colorless diamond produced at ever higher growth rate and low cost, large blocks of diamond should be available for a variety of applications.
"The diamond age is upon us," said Hemley.
I was going to get a diamond uprgade for Mrs. Plutarch, but decided it would be a lousy investment with new perfect fake diamonds being produced.
There are ways to test them for authenticity, I just can't think of the name at the moment. You can bet jewelers are not going to pay as much for the fake ones as they do the real ones. If it did come to the point that they couldn't tell, then they would probably just deal with reputable people, like DeBeers. jmo
See post 15, fastglock. I think DaGman meant to post to you.
Netizen wrote:
Probably not. They would stil be MAN MADE. Just like the man made emeralds. They are not real even though stores may tell you so. Just ask your insurance person. Some don't mind fake gems though and that's ok, too. :)
--> I guess this would be like the "gucci" knock offs they sell on the street corners, etc... why pay for the real thing when you can have "faux" ?
But, I wonder how much the processing itself costs.
''CVD diamonds cost well over one hundred dollars a carat to produce,'' according to info in this link: Link
Some people prefer real over synthetic. The choice is yours. I saw a show on these types of diamonds a while back. They still wanted a pretty stiff price for them even though they are synthetic. Not much savings at all. At that price one might as well get the real thing.
THank you, i went back and looked at the post. :)
Or watch crystal or (fill in the blank). The new problem will be the scuffs created when this material scrapes against formerly harder materials.
The fake ones aren't that cheap, that's why. If you want cheap and fake then go to QVC and get diamonique! lol
LOL, who ever suspected that one day, diamonds would show up in Jacker Jack boxes?
>>> once they're cut, how would you tell the difference?
The monopoly named DeBeers is definitely worried about the competition. I understand DeBeers is etching a microscope 'identifier' on their diamonds using lasers.
LOL! Do you realize that you used "reputable people" and "DeBeers" in the same sentence? Their whole business model is based on getting people to believe a lie.
And don't forget to order them in every size! Eventually, huge ones will be available. Think of it -- a giant diamond hood ornament on your Jaguar, with matching diamond gearshift/dash knobs. Even the bolt heads on your license plate fasteners.
>> Remember that natural diamonds are quite common and their high value is due only to DeBeers' monopoly on sales and distribution.
That is true. Diamonds would be inexpensive, if not for the monopoly and slick marketing of DeBeers. Why did diamonds become popular in the mid 1900's? DeBeers used Hollywood stars as marketing tools. If you are as old as I, you will recall the time when Hollywood stars were mystical -- and respected -- unlike the trash that dominates most of the film industry today.
I couldn't think of a better word to use when comparing them to the makers of fake gems. Miners dinn't seem right. You know what I meant though, I think.
So this 10 carat baby cost over $1 billion. I think your source is using out of date information or, it was a typo.
Good thing I postponed wedding-ring shopping, eh?
And just as quickly, the synthetic process will introduce flaws to mimic the naturally occuring ones under more and more powerful examining techniques. At least, that's my suspicion.
I'll bet all the folks who were "divested" and driven out of South Africa have been laughing up their sleeves at all this.
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