ROCKS:

             Any natural mass of mineral matter that makes up the earth's crust is called a rock. 

              Rocks are differentiate by size, colour and texture.

              There are three major types of rocks,  they are,

               1. Igneous Rocks

               2. Sedimentary Rocks 

               3. Metamorphic Rocks

Igneous Rocks:

               When Malton magma cools, it  solidifies and form a rock. This rock is called as igneous rocks. 

                There are two types of igneous rocks: 

                1. Extrusive Igneous Rocks 

                2. Intrusive Igneous Rocks

Extrusive Igneous Rocks:

                 When molten lava comes out the earth surface it cools down and became solid. Rocks are formed on earth's surface in this form called extrusive igneous rocks.

                   For example: Basalt

Intrusive Igneous Rocks:

                    When molten magma cools, solidifies beneath the earth's crust, it  form a rock called intrusive igneous rocks.

                     For example: Granite

                  

Sedimentary Rocks:

                      Rocks are roll down, crack and hit with each other and are broken into small fragments. The smaller particles called sediments.

                     These sediments are transported and deposited by wind, water, etc.

                     These loose sediments are compressed and hardened to form layers of rocks. These types of rocks are called sedimentary rocks.

                     For example: Sand stone

Metamorphic Rocks:

                      The Igneous and sedimentary rocks can change into metamorphic rocks under great heat and pressure.

                       For example: limestone changed into marbles.