Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
×
Earth Science

Natural Fluorine Does Exist ... In Smelly Rocks 80

scibri writes "Chemists have proved that a smelly rock is the only known place on Earth where fluorine exists in its elemental form, F2 (Abstract). The rock is antozonite, a calcium fluoride (fluorite) mineral that is dark violet or even black in colour, also known as fetid fluorite or stinkspar. Needless to say, this rock stinks. The pungent smell is given off when antozonite is crushed, and chemists and mineralogists have argued over the origin of the stench since the early nineteenth century. It turns out French chemist Henri Moissan, who first isolated fluorine in 1886, was right. The rock contains pockets of fluorine that are released on crushing."
This discussion has been archived. No new comments can be posted.

Natural Fluorine Does Exist ... In Smelly Rocks

Comments Filter:
  • by Anonymous Coward
    Just today I went to Autozone and bought a car air freshener!
  • by AlienIntelligence ( 1184493 ) on Friday July 13, 2012 @07:44PM (#40645331)

    Clues from previous experiments suggested how fluorine might be formed in the rocks. The experiments exposed artificial calcium fluoride to - and -radiation, and high-energy electron beams. The samples often turned violet, because the radiation was splitting calcium fluoride apart to form clusters of calcium ions. Subsequent tests showed that bubbles of fluorine gas were also forming in the lenses.

    The same process could explain the stench of antozonite, says Kraus. The mineral contains tiny amounts of radioactive uranium-238, which decays into -emitting daughter nuclides. The rocks have been lying around for 100 million years, says Kraus, which is enough time for the radioactive decay to produce the same effect as seen in the artificial fluorite experiments.

    Interesting stuff to a rock nerd.

    -AI

    • by Anonymous Coward

      This looked really weird until I realized my font doesn't include alpha or beta characters.
      Perhaps I have a pre-alpha release.

      • by Goaway ( 82658 )

        Nothing to do with your font. Slashdot is just completely broken and silently eats all non-ASCII characters.

      • This looked really weird until I realized my font doesn't include alpha or beta characters. Perhaps I have a pre-alpha release.

        The Greek letters in GP's post have decayed before you got to read them.

    • by dmbasso ( 1052166 ) on Friday July 13, 2012 @09:04PM (#40645667)

      The rocks have been lying around for 100 million years

      Heresy! God created them smelly 6 thousand years ago!

    • by Anonymous Coward

      http://www.youtube.com/watch?v=VX1qiQoASlw&feature=related

      Anything that bioaccumulates that is harmful in sufficient concentrations must be kept below very very low levels of intake, sufficient so that it cannot accumulate to harmful levels. Even after 40years! heck should we accept it if it took 80years?

      In southern india and many parts of africa the levels of flouride in the water naturally are so high that they suffer extreme health problems including skeletal fluorosis. http://video.google.com/videop

  • communists! (Score:3, Funny)

    by Anonymous Coward on Friday July 13, 2012 @07:48PM (#40645357)

    Do you realize that fluoridation is the most monstrously conceived and dangerous Communist plot we have ever had to face?

    • by Lumpy ( 12016 )

      "Do you realize that fluoridation is the most monstrously conceived and dangerous Communist plot we have ever had to face?"

      Shut up and drink more water comrade...

    • by Mal-2 ( 675116 )

      Do you realize that fluoridation is the most monstrously conceived and dangerous Communist plot we have ever had to face?

      Funny, I got a pamphlet from Pueblo, Colorado entitled, "Do you know what the queers are doing to our soil?" They're planting elemental fluorine to defoliate landing strips for gay Martians! You know what, AC, I like you. You're not like the other people, here in this trailer park.

  • by Anonymous Coward

    You're gonna bring out all the anti-flouride nuts.

    People so worried about a massive decades long goverment flouride consipracy that can be beat by buying a water filter....

    • People so worried about a massive decades long goverment flouride consipracy that can be beat by buying a water filter..

      Sorry, I don't understand. Are we talking about flourine or flouride? I'm 54 (and no chemist so I don't know the difference, please excuse me) and the water I grew up with was flouridated, the toothpaste I use also contains one of the above. To the poster below regarding black teeth. I still have all my teeth and they are not black. Daily brushing and flossing seem to have kept them i

      • Re:Now you did it... (Score:5, Informative)

        by wierd_w ( 1375923 ) on Friday July 13, 2012 @09:37PM (#40645815)

        Not a chemist either, just a chemistry nerd, but:

        First. Its "Fluorine", not "flourine". No ground up wheat is involved. :D (sorry for the nitpick. Its an honest mistake.)

        Second, "fluorine" is the elementary pure form. Pure fluorine is a covelently bound pair of fluorine atoms, much like pure oxygen is.

        Fluoride is a salt made with fluorine that does not contain oxygen. Eg, "sodium fluoride": a sodium atom ionically attracted to a fluorine atom.

        When oxygen is involved, you get "fluorite", and "fluorate", depending on the number of oxygen atoms involved.

        Natural fluorites and fluorides occur in groundwater in far higher concentrations than are medicinally useful. Typically, the concentration of fluoride ion required to help stabilize the calcium phosphate complex found in teeth against acid breakdown is less than 1% in solution. (Toothpastes are usually sufficient to get the primary benefit of topical fluoride use, and usually contain .2% fluoride ion in the form of sodium fluoride by weight. Fluoridated water is higher, because the time the water is in contact with teeth while drinking is considerably shorter.) You can have way higher than this in naturally fluoride contaminated water supplies.

        High levels of fluoride in drinking water causes abnormal tooth and bone formation, in a condition known as fluorisis. It causes discolored, and fragile teeth, as well as brittle bones that are especially prone to osteoporosis and other bone disorders. As such, the danger of overfluoridation is indeed quite real. However, you would have to regularly eat your toothpaste to have this condition. It is argued that children, the primary reported benefactors to fluoridated water operations, are notoriously bad at proper use of brushing and toothpaste use, and are at significantly higher risk of ingesting the toothpaste instead of spitting it out. In conjunction with fluoridated water, this results in a higher risk of permanent tooth deformities in adult tooth formation from the excess fluoride.

        In areas with already dangerous levels of fluoride present in the drinking water from natural sources, the use of a filter to remove the excessive ion concentration is not only beneficial, but highly recommended, as it can indeed cause severe and debilitating tooth and bone problems.

        The more you know!

        • When oxygen is involved, you get "fluorite", and "fluorate", depending on the number of oxygen atoms involved.

          One small nit, from another non-chemist chemistry nerd: this never happens. It does with other halogens (bromine, chlorine, iodine), because they can all be oxidized, and in fact combined with oxygen, to make stable oxyhalide anions. Fluorine don't play that; forced into company with oxygen, fluorine does the oxidizing, and oxygen gives up an electron or two. The resulting oxygen difluoride isn't an acid anhydride; mixed with water, it gradually decomposes into hydrofluoric acid and oxygen, instead of makin

          • Me too! I didnt think something as electronegative as fluorine could remain in elementally pure form outside of a constantly irradiated supernova gas cloud, or similarly exotic environment. it reacts with pretty much everything! (and when it does, it doesnt let go!)

            • by rs79 ( 71822 )

              "I don't want to say she was a turn off, but even flourine won't react with her"

        • Comment removed based on user account deletion
          • an exact ratio is a poor measure for what is an appropriate fluoride ion intake on a per-person basis.

            Different people absorb the ion at different rates upon ingestion, so while one person might develop fluorosis, another might not, despite having an identical diet, and an identical fluoride intake, even when measured in total milligram quantities.

            This is part of why fluoridation of drinking water is often a hotbutton issue, even among health experts and chemists. On one hand, there is a clear health benefi

            • And what about the guy who says that fluoride cuts up the enzymes that re-enamalize teeth?

              Healthy teeth are made of calcium and phosphate, according to Gerard Judd's old site (gerardjudd.com iirc - check archive.org)... Cavities are caused by acids which dissolve tooth enamel - these are either in foods (soda, etc), or produced by bacteria. Instead of dumping a highly reactive molecule in the water, one that contributes to osteoporosis in old women, wouldn't it be better to give kids the proper supplements

        • Not a chemist either, just a chemistry nerd, but:

          First. Its "Fluorine", not "flourine".

          It's "it's" not "its" for 'it is,' or is it?

          ...Sorry, I'd never correct something like that, but the urge to nitpick a nitpick is just too great. My apologies to all normal people. :)

        • Natural fluorites and fluorides occur in groundwater in far higher concentrations than are medicinally useful. Typically, the concentration of fluoride ion required to help stabilize the calcium phosphate complex found in teeth against acid breakdown is less than 1% in solution. (Toothpastes are usually sufficient to get the primary benefit of topical fluoride use, and usually contain .2% fluoride ion in the form of sodium fluoride by weight. Fluoridated water is higher, because the time the water is in contact with teeth while drinking is considerably shorter.) You can have way higher than this in naturally fluoride contaminated water supplies.

          You must have got your numbers seriously wrong. Of course the concentration is less than 1%, that would kill you rather quickly, you'd probably get a cardiac arrest. As far as I know, the concentration in treated water is somewhere around 1 ppm.

        • Fluorisis isn't the only danger to fluoride in the blood (and not used as a topical treatment) - The penial gland in the brain is the organ that fluoride collects the most in. It basically calcifies and prevents it from functioning. The penial gland is pivotal to the secretion of melatonin (and DMT when you sleep for those extra-real dream sequences) which affects sleeping patterns, the onset of puberty and seeing majesty (i.e. Trogdor). It's pretty important to our individual process of creativity and feel

      • neither; we're talking about fluoride and fluorine. i dunno how you ionized milled wheat.

        back on topic: you can overdose on fluoride which causes all sorts of bad things. the therapeutic dose is close to the fluorosis dose, so the recommended levels of fluoride have been reduced over the past few decades. i wouldn't really be surprised if there were some serious problems with the original dosage in some areas, from whence all of these conspiracy theories...

      • So..... instead of assuming that everyone knows the dangers, please educate me. That's an honest request actually.

        You can ignore the conspiracy idiots.

        The conspiracy theory centers around fluoride being an industrial waste product... so presumably somebody faked the bone/dental tests so that water companies would pay them to haul away their trash (fluoride).

        "Fluoride poisoning" is a real condition, but you need far more than you would get in tap water. In fact "Water Intoxication" is a real condition too,

        • by rs79 ( 71822 )

          Ectually, flourine molecules have a strategic role in their place in some psych meds. All it takes is one schizophrenic to find this out and overnight there's tens of thousands of anti-flouride crusaders on facebook.

      • Are we talking about flourine or flouride? I'm 54 (and no chemist so I don't know the difference, please excuse me

        Don't let that stop you from having extreme and strongly held opinions.

        It certainly doesn't prevent anyone else.

      • by idji ( 984038 )
        elemental Fluorine (found as F2) is nasty, it is so reactive it can eat/etch/oxidate glass and most metals. Just think about how noxious chlorine is, and it is MUCH worse and more toxic
        It is most fascinating, that the most oxidative (more powerful than anything else at stealing 1 electron, except perhaps PtF6-) substance we know is found in nature in this special environment. Nature was almost always there before us, including natural nuclear reactors in Gabon. Just think about how special elemental oxyge
  • that's just the way a hardcore commie works

    http://www.youtube.com/watch?v=Qr2bSL5VQgM [youtube.com]

  • I remember my geology professor telling us this exact thing back in the 80's. Was College level geology professors teaching as fact something that was only a theory?

    Why could they not have ran the same tests? Gas Chromatagraphs existed back then, so setting it up to crush a sample and then test the gasses released would have been trivial.

  • according to http://www.theodoregray.com/periodictable/Elements/009/index.s7.html [theodoregray.com] , its pretty difficult to make a container to store pure F2 gas, maybe this is a way to at least transport it, assuming you have enough of the rock, or can make more of it.

    Also, you smelt it? whats the safe distance you can get near this stuff (before/after you crush it) without doing nasty damage to yourself.

Keep up the good work! But please don't ask me to help.

Working...