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The AFU and Urban Legend Archive Science diamonds are a scientists best friend
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The AFU and Urban Legend Archive Science diamonds are a scientists best friend
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From: rrd@fc.hp.com (Ray Depew)
Newsgroups: alt.folklore.urban
Subject: Artificial diamonds: a book report
Date: 16 Jan 1998 20:29:44 GMT
One of the bad things about mortal life is that there's never enough time. I don't have enough time to read all the books I want to read, climb all the mountains I want to climb, learn all the things I want to learn and marry all the - sorry, I didn't mean to start discussing religion here. I wanted to talk about diamonds again.
Last year I accidentally discovered "The Most Beautiful Molecule : The Discovery of the Buckyball" by Hugh Aldersey-Williams, while wandering the stacks in the city library. Then around Christmastime, someone on AFU (it was <Yttrium@cris.com> on 1997/12/22) posted a pointer to "The New Alchemists: Breaking Through the Barriers of High Pressure" by Robert M. Hazen. The author acknowledged that the book was out of date when it went to print in 1993; that's how fast the technology changes. But it's an interesting book and sheds some light on Timothy Gershon's misinformed assertion that a scientist at Cambridge was coming up with a process for making artificial diamonds that would "bankrupt deBeers".
First, the book attempts to answer the question: "Who first made artificial diamonds?" The answer surprised me. (Hint: it's not Tracy Hall, although he gets all the credit, and the book explains why.)
A team in Sweden made the first artificial diamonds on Feburary 16, 1953. They subjected graphite to 83,000 atmospheres and unspecified heat generated by a thermite shell (barium peroxide & magnesium). They repeated their work on May 24 & Nov 25, and had the Nov 25 diamonds verified by an independent diamond expert. Strangely, they made no announcement until 1955, after the GE team's announcement, and provided no process details until Lundberg published a 1960 retrospective, so nobody had a chance to duplicate their efforts. They only produced a fraction of a carat of tiny diamonds, and their secret efforts to perfect the process were scooped by GE's public announcement in 1955, so they abandoned the project (well, actually, they sold out to deBeers). As a result of these misjudgements, they get no credit for the discovery but are "relegated ... to little more than a historical footnote."
At GE, a six-man team worked on the project for several years. GE's Herb Strong thought he had made diamonds on Dec 8-9, 1954. He started with carbon powder, iron foil & seed crystals, cooking them overnight at 50,000 atm and 1250 deg C (with some mysterious temperature excursions due to a faulty controller). The team found 2 crystals of dubious origin (could've been the seed crystals) embedded in the iron foil. One of the other team members said that they then "wasted weeks" trying unsuccessfully to repeat the experiment.
Only a week after Strong's run, GE's Tracy Hall made diamonds on Dec 16, 1954. He started with graphite, iron sulfide & seed crystals, but he needn't have bothered with the seed crystals. Cooking his sample at 100,000 atm, 1600 deg C for only 38 minutes, in a press different in design from Strong's, he made a mass of tiny diamonds. The experiment was successfully repeated by Hall and by independent GE researchers -- and by Percy Bridgman, who'd been trying unsuccessfully for years to make diamonds at Harvard. GE patented Hall's process, the Dept. of Commerce slapped a secrecy order on it, and so although they could announce the discovery in 1955, they couldn't disclose any details.
Hazen suspects that the GE team had made diamonds before then, but hadn't really known what to look for. The GE samples that would confirm this have been lost through carelessness, and so the world will never know.
(Here's an interesting tie-in to the "glass flows" thread: metallic hydrogen. Hazen talks for a chapter about the search for metallic hydrogen. He discusses how the research team of Mao and Hemley got tantalizingly close in September 1989, detecting a phase change at 2.5 million atmospheres and room temperature, where the hydrogen turned dark, a predicted first step towards metallization. They repeated the experiment several times and published an article, but they called it "dark hydrogen" because they weren't ready to go all the way and call it metallic hydrogen.
The Internet is a wonderful thing. At http://www.llnl.gov/PAO/NewslineStories/Hmetallization.html is a story of how Lawrence Livermore researchers were able to make metallic hydrogen at 1.4 million atmospheres and 3000 deg K. The pressure was lower than expected, probably because the temperature was higher. The researchers also reported that hydrogen at 3000 deg K is a liquid metal. So we're still looking for solid, metallic hydrogen.)
An intriguing paragraph in the closing pages of the book hints at something that could indeed "bankrupt deBeers"! In 1991, in the midst of the buckyball craze, a French trio headed by Manuel Nun~ez Regueiro quietly reported that they had made diamonds from buckminsterfullerene. The process is so simple and cheap that, if/when it is commercialized, anybody with a good banker can make diamonds.
Here's the recipe:
1. Buy some C60 buckminsterfullerene. A few dollars per pound. If you
can't buy it cheap, then make it:
needed, no heating. 3. Wash the product in concentrated nitric and other acids. RINSE WELL. 4. Et voila`.
Hazen says:
Many chemists predict that buckeyballs will soon be available for
a few dollars per pound. If so, it may well usher in a enw era
of diamond making. As the French team wrote in their Nature
article, "The high efficiency and fast kinetics at room
temperature suggest the possibility of using this transformation
for fabrication of industrial diamonds." Fast, cheap, no
complicated heating requirements, just a simple squeezer to
synthesize pounds of diamonds - buckeyballs could become a
diamond maker's dream.
Suppose that buckydiamonds could be made of a size and quality to rival natural gemstones. (Nun~ez's first one was clear and yellow, not black, so it's possible.) Then suppose that these buckydiamonds could be subjected to the computer-aided cutting and polishing currently under development at Cambridge. I can see how deBeers would be either worried ("now anybody can make diamonds!") or excited ("lower manufacturing costs means more profits!"). It all depends on how people more important than me play their cards.
Regards | "It does not do to Ray Depew rrd@fc.hp.com | leave a live dragon out of Integrated Circuits Business Division | your calculations." Hewlett Packard Co, Fort Collins, CO | -- Tolkien
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