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TYPES OF IGNEOUS ROCKS

Following are the two types of igneous rock:

Intrusive igneous rock: Extrusive igneous rock:
These rocks crystallize below the earth’s These rocks erupt onto the surface
surface resulting in large crystals as the resulting in small crystals as the cooling
cooling takes place slowly. takes place quickly.

Eg:-Diorite, granite, pegmatite Eg:-. Basalt, tuff, pumice

1) Granite

 When magma cools below the Earth surface it forms Granite.

 The rock consists, largely, of three minerals. They are Mica, Quartz and Feldspar.

 Granite is generally white or grey in colour, depending upon the content of different minerals
in it.
 It is very hard rock

 It is generally used for making statues and flooring of the houses.

2) Pumice

 When lava cools quickly on the Earth surface, it forms Pumice.

 It has many holes in it.