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Flawless Man-Made Diamonds
After decades of experimentation, scientists can finally grow diamonds that outshine even the rarest De Beers rocks.
What: Perfect single-crystal diamonds of more than two carats (the average engagement ring is less than a carat) churned out in a day. Scientists create the gemstones using a process called chemical vapor deposition (CVD), which grows diamond crystals one carbon atom at a time.
Why: The jewelry industry has shown great interest in ersatz versions of the 45-carat Hope diamond, but other uses could prove more lucrative. Using CVD, scientists will be able to cheaply mass-produce diamond semiconductors that are hundreds of times as powerful as their silicon counterparts.
Who: Russell Hemley of the Geophysical Laboratory of the Carnegie Institution of Washington and researchers at Apollo Diamond, Inc., in Boston, have produced the largest and some of the most flawless diamonds so far. And Europes Carbon Power Electronics consortium, led by Dutch diamond maker Element Six, has created a synthetic diamond diode, the first step toward working diamond semiconductors.
When: During the past year, scientists have mastered the ability to grow 10-carat single crystals with a color and clarity that surpass mined diamonds. Within a decade, theyll also be cheaper. Expect to see the first diamond semiconductors hit the market in 2011.
How To Grow a Diamond
1. Plant Seed
Start with a tray of flawless, button- size diamonds. Just as an oyster deposits layers of calcium atop sand grains to form pearls, these seeds serve as the base on which larger stones will develop.
2. Nourish It
Place the seeds in a microwave chamber, and feed them hydrogen and methane gases. When the temperature hits 1,300°F, the hydrogen combines with methane to produce a highly reactive form of carbon.
3. Watch It Grow
These carbon radicals rain down from the cloud of hot plasma and bond to the carbon on the surface of the seed. A new diamond crystal soon begins to form [diamond and seed, shown here].
4. Trim Stone
Once the diamond reaches the desired size (12 hours for a full carat), separate the newly grown diamond crystal from the seed. Cut and polish the stone like you would a mined diamond.
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What To Use It For
Jewelry
Gem-quality synthetics of various colors [above] are not new, but large colorless synthetics are. The De Beers diamond cartel is feeling the pressure: To make it easy for jewelers to distinguish between mined and lab-bred stones, De Beers has started engraving logos on mined diamonds.
Semiconductors
Fast processors generate lots of heat. Silicon semiconductors break down at around 250°F, but diamonds can take up to 1,300°. As a result, they can run as fast as 81 gigahertz without elaborate cooling mechanisms (the fastest silicon chips run at about 10).
Optics
Because of their heat conductivity and chemical stability, diamond lenses [facing page] transmit sharper laser beams at higher temperatures than zinc selenide, the industry standard. Look for diamond lenses in CO2 lasers used for precision cutting, welding and surgery.
FAQs
But arent they fakes?
No. Created stones have the same atomic structure as diamonds that form inside the earth, so they are real diamonds in every sense. They are optically, chemically and physically identical. In fact, since scientists start with seeds of the purest stone and carefully control the growing environment, they can systematically produce colorless rocks with far fewer impurities than most mined diamonds.
Are synthetics faster to grow?
No one knows for sure how long it takes diamonds to form inside the earth. Geologists do know, how-ever, that it takes millions of years for the earth to trans-port them to the surface, where they can be mined.
Why would anyone want a synthetic?
Man-made diamonds are cheaper and have fewer flaws than most mined diamonds. Also, some people are uncomfortable supporting companies that prop up the African warlords that control many of the diamond mines.
How cheap?
Apollo is already selling near-colorless synthetics that are a quarter of a carat in size for as little as $500 (versus $750 for a mined gem), and prices of bigger stones will plummet as mass manufacturing gets underway. Engagement-ring-size colorless diamonds will be up to 30 percent cheaper than their mined equivalents.