How are minerals formed in igneous and metamorphic rocks?

Q.2 (iii):- How are minerals formed in igneous and metamorphic rocks?

 

Answer:-

In igneous and metamorphic rocks, minerals occur in cracks, crevices, faults and joints. They are formed when minerals in liquid or molten and gaseous forms are forced upward through these weak zones (cavities) towards earth’s surface. They cool and solidify as they rise towards the surface. Tin, copper, zinc, lead and diamond etc. are various minerals found in igneous and metamorphic rocks.