Are we talking about high mountains spewing hot lava? No. Those are volcanoes. We are talking about the rocks that are used as fuel that can be used to cook food or to run engines or to build roads. These are rocks that burn. Have you ever heard of them?

Long ago, some black stones were discovered and soon they began to be sold in the city markets as “rocks that burn”. Initially, people were suspicious. After all, how come ordinary looking rocks could keep their homes warm? But slowly, people realized that these rocks were unique. They produced heat when burnt. We now know these rocks as “Coal”. Little did people know at that time that coal would become the largest source of energy for humans and also stay like that for many years more than one could count.

Although coal is called a rock, but did you know that it was once a tree! Yes, it is made out of trees. Let explore how trees turned into rocks. Millions of years ago there were hot and swampy forests spread out all over the world. Since the soil was extremely moist and spongy, the trees just clung together and became one. When these trees decayed, more trees and ferns took their place. Layers and layers of this decayed material kept collecting in the swampy mud for many years.

Rivers, lakes, and seas collected other things over the decayed layers of trees. Earthquakes pushed these layers even deeper over a period of time. These compressed layers of decayed material slowly turned into coal.

It is clear now that all of this coal is found deep under the ground, the question remains: How does one get it out?

Can we dig our backyard and find coal?

Nah! Before beginning to dig people have to know if the area has coal hidden underground. Then, using ultra powerful machinery, the coal deep under is dug and pulled out. The process of pulling coal out is called “mining”.

Coal mining has been a hugely important industry ever since it first started. And it has stayed that way.

People who work in the coal mines are called miners. It is not easy working in mines. The shafts are dark, have terribly little air to breathe and there is always the danger of getting hurt. However, these men are brave and go on with their work of reaching out to the coal and pulling it out for us to use.

• Coal is also called black gold.
• Sometimes diamonds are also found inside coal mines.
• The first time coal got actually mined underground was in year 1575, in Scotland. Before that much of the coal was extracted using strip mining, along sea shores. Those were then called sea coal. Interesting!