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Classifying rocks

  1. profile image0
    Ruach Eishposted 7 years ago

    Can anyone tell me how to tell the difference between igneous, sedimentary and metamorphic rocks?

    1. glowingrocks profile image55
      glowingrocksposted 7 years agoin reply to this

      This one is impossible.There is no simple answer to this question.I can give you two examples which are usually true for identification.If there are fossils in the rock it usually is sedimentary.Many metamorphic rocks have distinct banding or lines in them.There are however exceptions in both cases.

      1. profile image0
        Ruach Eishposted 7 years agoin reply to this

        yes - its the exceptions which were bugging me!!!  Thankyou though, and I shall keep practising at identifying rocks (Im a relative beginner) one assumes my skills will improve with practise like with anything.

  2. Evan G Rogers profile image76
    Evan G Rogersposted 7 years ago

    Pretty easy stuff.

    Igneous = Lava that cooled off. Black. Smooth. Near volcanoes.

    Sedimentary = loose minerals that, basically, dehydrated into a rock. Most of the rocks around. If you look closely, you'll see layers. Many are brittle, but they don't have to be.

    Metamorphic = Other rocks that have been screwed up via heat and pressure. Take a rock and crush it while heating it up... you'll get something weird.

    http://www.classzone.com/books/earth_sc … page01.cfm