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A rock that rattles?

  1. Apr 6, 2010 #1
    A rock that rattles??


    i have this rock that my father gave to me before he died.

    its an egg shaped rock but i doubt its an egg of any kind but i dont know, and when you shake it it rattles as if there is something inside of it. I am wondering what could be inside of it.

    Does anyone have any idea what might be inside of it?? or what might this rock be?

    Thank you.
  2. jcsd
  3. Apr 6, 2010 #2
    Re: A rock that rattles??

    Insufficient information. Try posting a picture, preferably with a ruler, so that we can see the size. Without having seen it, one possibility is that it might be a geode. If so, the likkeliest thing inside would be a piece of quarta crystal. You might try http://en.wikipedia.org/wiki/Geode for a description. Don't rattle it too hard; you are likely to spoil it.



    PS, Why is this question not in the earth sciences forum?
  4. Apr 8, 2010 #3
    Re: A rock that rattles??

    Unless it is an artifical construct then my vote is also for geode. Frankly I cannot think of anything else it could be.
  5. Apr 13, 2010 #4


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    Re: A rock that rattles??

    I found an egg-shaped rattling rock when I was 7. From rock books, I decided it was a geode.
  6. May 28, 2010 #5


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    Gold Member

    Re: A rock that rattles??

    mk has it! This egg shaped rock is probably a geode which is a hollow rock formation that may have had some of its interior shaken loose... and now it rattles when it shakes. Could make a good earthquake alarm system...!
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