We may feel we walk on solid ground but when a volcano erupts or an earthquake rumbles the ground beneath us, we know that the inside of the Earth is involved in its own active process. When a volcano erupts, hot, liquid rock comes spewing out of the interior of the Earth with great force. Its temperatures can reach up to 2192 F°.

As this liquid slowly cools rock forms and within the rock are found a huge variety of minerals. Geologists have identified approximately 3500 unique minerals. These minerals are the building blocks of our bodies, the food we eat, and of all the solid objects in the world.

Science - Mysteries - The Earth