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TOPIC: The Diamond Age


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RE: The Diamond Age
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Researchers at the Carnegie Institution have developed a new technique for improving the properties of diamonds-not only adding sparkle to gemstones, but also simplifying the process of making high-quality diamond for scalpel blades, electronic components, even quantum computers. The results are published in the October 27-31 online edition of the Proceedings of the National Academy of Sciences.
A diamond may be forever, but the very qualities that make it a superior material for many purposes-its hardness, optical clarity, and resistance to chemicals, radiation, and electrical fields- can also make it a difficult substance with which to work. Defects can be purged by a heating process called annealing, but this can turn diamond to graphite, the soft, grey form of carbon used in pencil leads. To prevent graphitisation, diamond treatments have previously required high pressures (up to 60,000 times atmospheric pressure) during annealing, but high pressure/high temperature annealing is expensive and there are limits on the size and quantities of diamonds that can be treated.

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Blue diamond
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Blue diamond fetches record price
A blue diamond, smaller than a penny, sells for 10.5 million Swiss francs at auction in Geneva to an anonymous buyer.

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M-carbon
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A new ultra-hard form of carbon may exist between graphite and diamond.
Carbon can exist in a form halfway between graphite and diamond, say researchers in China and the United States. And they believe this stuff is as hard as diamond itself.

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A rare blue diamond which could set a world record price per carat when it is sold in May has gone on show in London.
Smaller than a penny piece, it is worth between $5.8m (3.9m) and $8.5m (5.7m) according to estimates by its sellers.
It weighs 7.03 carats and is one of only a handful of blue diamonds in existence in the world.


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Diamonds
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A team in the US has brought the world one step closer to cheap, mass-produced, perfect diamonds. The improvement also means there is no theoretical limit on the size of diamonds that can be grown in the lab.
A team led by Russell Hemley, of the Carnegie Institute of Washington, makes diamonds by chemical vapour deposition (CVD), where carbon atoms in a gas are deposited on a surface to produce diamond crystals.

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Scientists grow bigger, better diamonds
Using chemical vapour deposition, gems can be grown very rapidly
If you thought that rock on the ring in the window of Tiffany's was big and beautiful, the diamonds treated in labs with a newly-developed method will really blow you away.

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For centuries, human beings have been entranced by the captivating glimmer of the diamond. What accounts for the stunning beauty of this most precious gem?
As mathematician Toshikazu Sunada explains in an article in the Notices of the American Mathematical Society, some secrets of the diamond's beauty can be uncovered by a mathematical analysis of its microscopic crystal structure. It turns out that this structure has some very special, and especially symmetric, properties. In fact, as Sunada discovered, out of an infinite universe of mathematical crystals, only one other shares these properties with the diamond, a crystal that he calls the "K_4 crystal". It is not known whether the K_4 crystal exists in nature or could be synthesised.

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Peanut butter is being turned into diamonds by scientists with a technique that harnesses pressures higher than those found at the centre of the earth.
Edinburgh University experts say the feat is made possible by squeezing the paste between the tips of two diamonds creating a "stiletto heel effect".
The scientists also revealed they can turn oxygen into red crystals using the same method.
Demonstrations take place at Royal Society exhibition shows from 2 July.

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Extreme pressures
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Generating pressures at the cores of giant planets

By combining the two, we can get to higher pressures and much higher densities than either of the methods alone

A laser vaporises a diamond cell, inducing a shock wave that produces pressures over 10 million times atmospheric pressure, greater than the pressure at Earth's core.
Combining diamond anvils and powerful lasers, laboratory researchers have developed a technique that should be able to squeeze materials to pressures 100 to 1,000 times greater than possible today, reproducing conditions expected in the cores of supergiant planets. Until now, these pressures have only been available experimentally next to underground nuclear explosions.

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If youve ever wondered about the ultimate fate of the universe, Lawrence Krauss and Robert Scherrer have some good news...sort of.
Writing in the journal Physical Review D, the two physicists show that matter as we know it will remain as the universe expands at an ever-increasing clip. That is, the current status quo between matter and its alter ego, radiation, will continue as the newly discovered force of dark energy pushes the universe apart.

"Diamonds may actually be forever. One of the only positive things that has arisen from the dark-energy dominated universe is that matter gets to beat radiation forever!" - Lawrence Krauss, professor of physics and astronomy at Case Western Reserve University (CWRU) who is spending the year at Vanderbilt.

Although this may not sound surprising, it actually runs contrary to conventional wisdom among cosmologists. Today, there is more matter than radiation in the universe. But there were periods during the early universe that were dominated by radiation due to particle decays. The generally accepted view of the distant future has been that ordinary matter particles protons and neutrons in particular will gradually decay into radiation over trillions upon trillions of years, leaving a universe in which radiation once again dominates over matter; a universe lacking the material structures that are necessary for life.

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