Page 219 - New Medley 5 Semester 2

 Conglomerate rocks: ese rocks are made of sand and pebbles which are

held together with minerals like silica and calcium carbonate. ese rocks
are either grey or orange in colour. Conglomerates are sometimes used as

ornamental stones.

 Gypsum rocks: ese rocks are very so and are made of sulphate minerals.

Gypsum is used to make plaster of Paris, casts and moulds.

 Shale rocks: ese rocks are made of clay. Shale rock is used to make bricks
and tiles.

Sandstone Limestone Conglomerate Gypsum Shale

Metamorphic rocks

Metamorphic rocks are formed by the transformation of either igneous rocks or
sedimentary rocks due to intense heat and pressure caused by overlying layers

of rocks.

ere are many types of metamorphic rocks.
 Marble: It is formed by the metamorphosis of a
sedimentary rock, called limestone. It is cut and

polished to give it a very smooth surface. Marble
is used to make buildings and statues. It comes

in many colours besides white and black. e Taj

Mahal in Agra is built of white marble. Taj Mahal

 Slate: It is formed by metamorphosis of shale, a sedimentary rock. It is shiny

and can split into thick sheets. It is grey or black in colour. Slate is used for
making blackboards, roofs and stone walls.

 Quartzite: It is formed

by the metamorphosis
or transformation of

sandstone. Quartzite
is used for making

statues. Marble Slate Quartzite

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