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Metamorphic Rocks
        Sometimes physical and chemical changes due to heat and pressure lead to transformation

        in the igneous and sedimentary rocks. This results in complete alteration and formation
        of new rocks. Such rocks are called metamorphic rocks. Some common examples of
        metamorphic rocks are slate, gneiss, quartzite and marble.




         1.  Slate: It is formed from shale. It also

              exists  in  thin  layers  which  makes  it
              an  ideal  roofing  material  and  is  used
              in making bricks, cements, slates
              for  children  and  blackboards  for                                    Slate

              classrooms.

         2.  Gneiss: It is transformed granite
              with light and dark bands of different
              thickness and length. It is a very

              useful rock, used for making building
              material.
                                                                                     Gneiss
         3.  Quartzite:  It  is  formed  by  the
              transformation of sandstone. These are
              hard rocks that contain iron, quartz and

              silica. It is not easily broken. Quartzite
              is  used  in  making  statues,  floorings
              and stairs. It is also used in glass and                             Quartzite
              ceramic industries.


         4.  Marble:  Marble is formed from
              limestone. Limestone undergoes changes
              to form marble. It is cut, polished and
              made  very  smooth.  It  is  used  to  make
              buildings. The Taj Mahal in Agra is built

              from  white  marble.  Marble  floorings
              enhance  the  beauty  of  a  building  as
              they  reflect  light.  Artists  have  carved

              beautiful  designs  on  marble  rocks  to
              create magnificent monuments.
                                                                          Taj Mahal (Marble)






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