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I had an interesting rock

  1. Feb 24, 2009 #1
    I found an interesting rock in a river bed in Arizona once. I think this rock would prove that the earth is much more than 10,000 years old as creationists like to believe. It was a piece of conglomerate. It had been rounded in the river bed, about 10" across. The interesting thing was that it had a nice red aggregate that looked like red concrete (it wasn't, this stuff was in many places) but the neat part was that in the aggregate were a bunch of stones a couple inches across that themselves were smooth and rounded from a river before they were formed into the conglomerate, they look like granite. Those stones must have been rounded in a river tens of thousands of years ago, maybe hundreds of thousands or more, before they were buried and made into conglomerate. And the rock I found was rounded from being in the river bed who knows how long, the aggregate was not soft at all, but it must have been a long time because I never saw water there while I was there for a few years. I found some of this stuff on one of the mountains around Phoenix too so it isn't concrete and I know conglomerate when I see it.

    Anyone have an idea how old this must be? Unfortunately I don't have it anymore, someone stole it. My first pet rock.. sob
    (this is probably in the wrong forum, sorry)
    Last edited: Feb 25, 2009
  2. jcsd
  3. Feb 24, 2009 #2


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    Staff: Mentor

    In my yard are rocks with fossils from 440 million years ago. Sounds like an interesting rock. I have one that I think is a type of quartz, and on one side the quartz is like it is in thin strips over what appears to be petrified wood, with parts of the wood exposed were the rock doesn't cover it. But the rock strips are pretty thick and close together, so I can't get a good look at what is inside. I need to have it looked at someday, I'm interested in what it is.

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    Last edited: Feb 24, 2009
  4. Feb 25, 2009 #3
    Pretty cool to have that stuff in your yard.
  5. Feb 25, 2009 #4
    Once you find an interesting rock or fossil it is easy to get hooked.There is a beach that I visit regularly and I like to stroll along looking for belemnites and other interesting things.My best find was was a strange shaped greyish rock with a mass of about 5Kg.I took it to a local museum and they identified it as being an elephants vertebra and about half a million years old.Apparently elephants and other animals walked to the U.K. during the ice ages.My elephant bone makes a great door stop.
  6. Feb 26, 2009 #5


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    Gold Member

    I haven't a clue how old your rock is I'm afraid. It could be pretty much any age. Your best bet is to find out a bit more about the area you found it in. A geological map would be a good place to start.
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