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Science

Harder-Than-Diamond Natural Carbon Crystals Found 250

Posted by kdawson from the twinkle-twinkle dept.
HikingStick tips a piece from the science desk at MSNBC.com about a new, naturally occurring form of carbon found in a meteorite fragment. "Researchers were polishing a slice of the carbon-rich Havero meteorite that fell to Earth in Finland in 1971. When they then studied the polished surface they discovered carbon-loaded spots that were raised well above the rest of the surface — suggesting that these areas were harder than the diamonds used in the polishing paste... [G]raphite layers were shocked and heated enough to create bonds between the layers — which is exactly how humans manufacture diamonds... [The research] team took the next step and put the diamond-resistant crystals under the scrutiny of some very rigorous mineralogical analyzing instruments to learn how its atoms are lined up. That allowed them to confirm that they had, indeed, found a new 'phase' or polymorph of crystalline carbon as well as a type of diamond that had been predicted to exist decades ago, but had never been found in nature until now."
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Harder-Than-Diamond Natural Carbon Crystals Found More

Harder-Than-Diamond Natural Carbon Crystals Found

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  • One thing I don't get... (Score:5, Interesting)

    by Looce ( 1062620 ) * on Tuesday February 02, 2010 @07:46PM (#31002934) Journal

    ... is why human-made diamonds, made the same way as that carbon-rich rock was discovered, are not harder than natural diamonds - at least, the summary seems to imply this. If it's graphite in both cases, then shouldn't both be harder than diamonds?

    • Re:One thing I don't get... (Score:5, Informative)

      by Kneo24 ( 688412 ) on Wednesday February 03, 2010 @06:13AM (#31007770)

      The very end of the article suggests that they are harder than regular naturally occurring diamonds.

      However, there is no way at the present to compare them to the artificial ultra-hard diamonds known as lonsdaleite and boron nitride, Ferroir said.

      • So, are these naturally-ocurring aggregated diamond nanorods (ADNRs)?

      • Re:One thing I don't get... (Score:5, Informative)

        by badfish99 ( 826052 ) on Wednesday February 03, 2010 @07:28AM (#31008144)

        However, there is no way at the present to compare them to the artificial ultra-hard diamonds known as lonsdaleite and boron nitride, Ferroir said.

        Boron nitride is not diamond at all, and lonsdaleite is described by Wikipedia as an allotrope of carbon that is found in meteorites and is harder than diamonds. Perhaps these people have just re-discovered something that was already known.

        • Re: (Score:3, Insightful)

          by AtomicOrange ( 1667101 )
          That... or Wikipedia got /.ed by some gung-ho reader that wanted to edit something that wouldn't get immeadiately marked as irrelevant.
        • ... or it's not something that occurs naturally in nature - it's our first verifiable alien artifact - a Cylon base ship hull fragment ,,,

      • Re:One thing I don't get... (Score:5, Informative)

        by Sockatume ( 732728 ) on Wednesday February 03, 2010 @07:50AM (#31008242)

        They've got an odd definition of "diamond" there: boron nitride has no carbon in it. It's a chemical analogue of diamond, in that you turn half the C atoms (atomic number 6) into B (atomic number 5) and the others into N (atomic number 7). B-N compounds are fun analogues of C compounds but it's a bit of a stretch.

    • Re: (Score:2)

      by RobVB ( 1566105 )
      Perhaps these crystals were shocked and heated more or in another way than human-made diamonds.

    • Re:One thing I don't get... (Score:4, Informative)

      by jandersen ( 462034 ) on Wednesday February 03, 2010 @07:33AM (#31008166)

      ... not harder than natural diamonds.

      That is because what they are (or should be) talking about is not hardness, but mechanical strength. Black diamonds are not harder, but because they consist of microscopic crystals, they don't have the convenient break lines of monocrystals, and therefore are more difficult to process. See:

      http://www.sciencedaily.com/videos/2007/0612-mystery_diamonds.htm [sciencedaily.com]

    • Re: (Score:2, Insightful)

      by __aamnbm3774 ( 989827 )
      I have no idea where you are getting that from. Sounds like some 1970s flub.

      In the past, you could tell artificial diamonds from natural ones because of imperfections, but with today's technology, you can't tell even with a microscope.

      Get some up to date info buddy!!

      • Re:One thing I don't get... (Score:4, Interesting)

        by IWannaBeAnAC ( 653701 ) on Wednesday February 03, 2010 @10:48AM (#31009648)
        Actually, you can tell, but in the opposite sense: it is exceptionally rare to get a natural diamond that has absolutely no imperfections; even the best usually have some minor flaw. On the other hand, it is relatively common to produce an artificial diamond that is flawless. De Beers and other companies have gone to quite some lengths to keep these diamonds away from the consumer market.

    • Re:One thing I don't get... (Score:4, Insightful)

      by dziban303 ( 540095 ) <dziban303@NoSpaM.gmail.com> on Wednesday February 03, 2010 @10:03AM (#31009122) Homepage
      Once again the news media gets something very basic very wrong. From TFA's headline:

      Crystalline carbon has never been found in nature until now

      Uhm, what do you think a fucking diamond is? Chopped liver? No. Chicken dinner? No. Random collections of carbon atoms in no particular order? No. It's a crystal. Of carbon. Crystalline carbon.

      BUT WAIT!! -- There's more! What about pencil lead!? Wow-it, too, is a form of cabon? In a crystal lattice?

      Idiot science reporters should go back to covering the MTV music awards.

      • Not only that...

        they discovered carbon-loaded spots that were raised well above the rest of the surface — suggesting that these areas were harder than the diamonds used in the polishing paste

        You know the old saying about running from bears? You don’t have to be faster than the bear; you just have to be faster than your buddy... remember that one?

        What they just said is, if you escape, it suggests that you were faster than the bear.

        • What they just said is, if you escape, it suggests that you were faster than the bear.

          If there were a multitude of bears pursuing you all and repeatedly applied with the intention of consuming you all equally, with the common result that everyone who is slower than a bear is devoured regardless of their speed relative to each other, then that's exactly what it would imply.

          That's what you're doing when you're polishing. Yes you can polish down softer materials more than harder ones, but then on the next pas

          • That's what you're doing when you're polishing. Yes you can polish down softer materials more than harder ones, but then on the next pass the raised harder material, if softer than what you're polishing it with, should also be worn down.

            They didn’t say it wasn’t worn down. They said it was worn down less than the surrounding areas.

            It’s harder. It wears more slowly. This has no relevance to whether or not it’s harder than the polishing grit.

            • They didn't say it wasn't worn down. They said it was worn down less than the surrounding areas.

              They said it was "raised well above the surface", which means that it wasn't worn down even after repeated application of the polish.

              If it wasn't harder than the polish, then the fact that it was raised would mean it would be worn down faster than the areas around it, so that it would quickly become level with the rest. That's how polishing works.

              It's harder. It wears more slowly. This has no relevance to whethe

            • You're making a semantic argument. Go grind a composite material with a sanding block. As long as the block is flat and held level, the entire substance is ground flat evenly, regardless of relative hardness ratings within the composite. Nothing "raised well above".

            • Re: (Score:2)

              by Gilmoure ( 18428 )

              But is it harder than a bear. Or deBeers? And if 'de Bears' were to play 'de Bulls'...

      • THIS crystalline carbon has never been found... (Score:5, Insightful)

        by Chris Burke ( 6130 ) on Wednesday February 03, 2010 @11:43AM (#31010386) Homepage

        If the headline was about a musician granting an interview, and the sub-header was "Famous performer never interviewed before", you wouldn't be scoffing "What? You mean no famous performer has ever been interviewed? Well I have a thousand back issues of Rolling Stone that would disagree!"

        What they're saying is that they have discovered a crystalline carbon, and it is something never seen in nature before. The sentence is accurate.

        Yes the truncated verbal style often used in headlines may have made it less clear than it could have been by the simple expedient of adding "This".

        Nevertheless, this is a perfect example of why I find pedantry to be so useless outside of technical fields where precise meanings not only exist but are required. Because more often than not, pedantry is just a way to fail to understand what is being said.

  • As the saying goes... (Score:5, Funny)

    by Black Parrot ( 19622 ) on Wednesday February 03, 2010 @06:44AM (#31007932)

    That allowed them to confirm that they had, indeed, found a new 'phase' or polymorph of crystalline carbon as well as a type of diamond that had been predicted to exist decades ago, but had never been found in nature until now.

    "Polymorphs of crystalline carbon are forever."

  • The remnants of my empire (Score:4, Funny)

    by Ceriel Nosforit ( 682174 ) on Wednesday February 03, 2010 @06:47AM (#31007952)

    And so a remnance of my empire once vast and impenetrable falls from the sky. Damn you Flash Gordon. Eventually I will get off this rock.

  • Mohs Scale of Hardness (Score:5, Funny)

    by L4t3r4lu5 ( 1216702 ) on Wednesday February 03, 2010 @06:47AM (#31007954)
    Now it goes all the way to 11.

    • Re:Mohs Scale of Hardness (Score:5, Funny)

      by RobVB ( 1566105 ) on Wednesday February 03, 2010 @06:56AM (#31007984)
      That's 1 harder!

    • Re: (Score:3, Insightful)

      by WGFCrafty ( 1062506 )
      Well since diamonds were used as the reference on the scale, being the "hardest" of everything known. Yes, either the scale should go to 11, or diamonds should be lowered. The scale seems to be pretty arbitrary though, just what scratches what.

      According to the wiki article:

      Since the invention of the scale, there have been reports of materials harder than the highest mineral on the scale, diamonds; so the Mohs scale may be changed in the future.

      And the reference is:
      T. Irifune, A Kurio, S. Sakamoto, T. Inoue, H. Sumiya "Ultrahard polycrystalline diamond from graphite" Nature 421 (2003) 599 [nature.com]

      A big meh to this slashdot story.

      Nature summary:

      Polycrystalline diamonds are harder and tougher than single-crystal diamonds and are therefore valuable for cutting and polishing other hard materials, but naturally occurring polycrystalline diamond is unusual and its production is slow. Here we describe the rapid synthesis of pure sintered polycrystalline diamond by direct conversion of graphite under static high pressure and temperature. Surprisingly, this synthesized diamond is ultrahard and so could be useful in the manufacture of scientific and industrial tools.

      • Re: (Score:3, Interesting)

        by WGFCrafty ( 1062506 )
        Upon re-reading, the new ones are completely natural, not synthetic polycrystalline diamonds.

        It is interesting that there has been a substance created harder than regular diamonds that has been published for seven years! I figured there would be saw blades everywhere which advertised "new, better than diamond tipped!"

        • It is interesting that there has been a substance created harder than regular diamonds that has been published for seven years! I figured there would be saw blades everywhere which advertised "new, better than diamond tipped!"

          Depends on how expensive/difficult to make/etc. the new 'diamonds' are. They could be too expensive to economically make. They could be so expensive that they are only used in specialized industrial/commercial applications. (I.E. people willing to pay seriously big, big bucks per bl

      • The actual hardness may actually be a 10.5 or 10.7 or 12. My guess is that they won't arbitrarily call this new structure 11 simply because it is harder than a 10. There may yet be even harder structures, or structures harder than diamond but softer than this.

        • Re:Mohs Scale of Hardness (Score:4, Informative)

          by AndersOSU ( 873247 ) on Wednesday February 03, 2010 @10:07AM (#31009172)

          The Mohs hardness is ordinal, not linear, so until unless this item is added to the scale it will have an undefined Mohs hardness. Actual engineers use Brinell hardness or something similar.

          • Actual engineers use Brinell hardness or something similar.

            What are you going to use as an indenter? Besides, that's a different measure of hardness; resistance to abrasion is different than indent hardness.

  • Old news... (Score:2, Funny)

    by Anonymous Coward

    RPGers around the world had known this for years: a meteorite sword is better than a diamond sword.

  • Lonsdaleite (Score:5, Informative)

    by mdsolar ( 1045926 ) on Wednesday February 03, 2010 @07:43AM (#31008212) Homepage Journal
    The article mentions hexagonal diamond (lonsdaleite) as an artificial form of diamond, which it is with a very interesting low energy formation method, but it was first found in nature in the Canyon Diablo Meteorite in 1967. http://en.wikipedia.org/wiki/Lonsdaleite [wikipedia.org] Pure lonsdaleite should be harder than regular diamond. I wish the article has said a little more about the crystal structure the researchers had found. That the energy required to make lonsdalite is low has interesting implications since the quantity needed to replace structural steel needs only about 1/280 of the energy needed to make the steel. http://mdsolar.blogspot.com/2008/01/anaximenes-way.html [blogspot.com]

  • Another way to make harder than normal diamonds (Score:4, Informative)

    by Aargau ( 827662 ) on Wednesday February 03, 2010 @08:11AM (#31008336)
    One can also make diamonds harder by isolating and using heavier isotopes. A diamond of purified carbon-13 is harder than a mix of 12,13,14. Man-made diamonds can actually be harder than naturally occurring ones.

  • Londsaleite or not? (Score:2, Informative)

    by physburn ( 1095481 )
    If the substance they found in the meteorite is indeed harder than carbon, then it probably isn't Londsaleite, as Londsaleites only as a Moh hardness of 7 to 8, where Diamond is 10 on the Moh scale. Shocked graphite with bonds between the layers certainly sounds a lot like Londsaleite though, but that wouldn't be a new form of Carbon. Apparently a theoretically perfect Lonsdaletite [wikipedia.org] crystal would be 58% harder than diamond, but why would the meteorite crystal be likely to have a near perfect structure.

    --

    • > If the substance they found in the meteorite is indeed harder than carbon,
      > then it probably isn't Londsaleite...

      I don't see that they claimed that it is.

  • Simple explination (Score:3, Funny)

    by Rooked_One ( 591287 ) on Wednesday February 03, 2010 @09:37AM (#31008886) Journal
    Since there is no such thing harder than diamonds on earth, and we cannot create anything harder, then it must have been aliens who sent us the meteorite with a substance so hard that it would...

    1- Make it to us through space

    2-have encoded within it their history

    3- then to be lost when we started grinding away on the bloody thing.

    -tom cruise.

  • Journal Article (Score:3, Informative)

    by Drache Kubisuro ( 469932 ) on Wednesday February 03, 2010 @11:08AM (#31009966) Homepage Journal

    For those that are interested in considering scientific paper without the media filter:

    Ferroir, Tristan, Leonid Dubrovinsky, Ahmed El Goresy, Alexandre Simionovici, Tomoki Nakamura, and Philippe Gillet. 2010. Carbon polymorphism in shocked meteorites: Evidence for new natural ultrahard phases. Earth and Planetary Science Letters 290, no. 1-2: 150-154. doi:10.1016/j.epsl.2009.12.015. http://linkinghub.elsevier.com/retrieve/pii/S0012821X09007389 [elsevier.com].

    I sure wish that secondary sources properly cited primary sources, even if they are only interviewing the main scientist involved. Giving the journal name and date as Discovery News did is a good step, though.

  • I need to make a minor adjustment to my Mohs scale.

  • link to orign article (Score:4, Informative)

    by cinnamon colbert ( 732724 ) on Wednesday February 03, 2010 @11:12AM (#31010016) Journal
    found here
    http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V61-4Y4XCTH-3&_user=10&_coverDate=02%2F15%2F2010&_rdoc=18&_fmt=high&_orig=browse&_srch=doc-info(%23toc%235801%232010%23997099998%231609118%23FLA%23display%23Volume)&_cdi=5801&_sort=d&_docanchor=&_ct=26&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=ae24ceb289eae1dcc9bc6870f3192dc2 [sciencedirect.com]
    And this is the abstract A slice of the Haverö meteorite which belongs to the ureilite class known to contain graphite and diamond was cut and then polished as a thin section using a diamond paste. We identified two carbonaceous areas which were standing out by more than 10 m in relief over the surface of the silicate matrix suggesting that the carbonaceous phases were not easily polishable by a diamond paste and would therefore imply larger polishing hardness. These areas were investigated by reflected light microscopy, high-resolution Field Emission SEM (FESEM), energy-dispersive X-ray (EDX) analysis, Raman spectroscopy, and were subsequently extracted for in situ synchrotron microbeam X-ray fluorescence (XRF), imaging and X-ray diffraction (XRD). We report here the natural occurrences of one new ultrahard rhombohedral carbon polymorph of the R3m space group which structure is very close to diamond but with a partial occupancy of some of the carbon sites. We also report the natural occurrence of the theoretically predicted 21R diamond polytype with lattice parameters very close to what has been modelized. These findings are of great interests for better understanding the world of carbon polymorphs and diamond polytypes giving new natural materials to investigate. These natural samples demonstrate that the carbon system is even more complex than what is currently thought based on ab initio static lattice calculations and high-pressure experiments since this new ultrahard polymorph has never been predicted nor synthesized.

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