___________ are also called primary rocks.

When the magma solidifies with in the earth's crust it cools is called ___________.

___________ are subjected to mechanical weathering  .

___________ have higher percentages of oxides of denser elements and silica content varies between 40 to 60 percent.

The word 'Igneous' is derived from the  __________ word.

___________ are hard and resistant to erosion.  

___________ are light in weight.

___________ are usually dome shaped with no definite floor.

____________ rocks do not contain fossils.

Based on their origin, the igneous rocks are classified into ________ types.