Almost everything that we use in our daily life, from a tiny pin to a towering building or a big ship, all are made from minerals.
The railway lines and the paving of the roads, machinery, implements and tools too are made from minerals. Cars, buses, trains, aeroplanes are manufactured from minerals and run on power resources derived from the earth.
Even the food that we eat contains minerals. Toothpaste that cleans our teeth uses abrasive minerals like silica, limestone, aluminium oxide and various phosphate minerals for the cleaning purpose.
In conclusion we can say that in all stages of development, human beings have used minerals for their livelihood, decoration, festivities, religious and ceremonial rites.
The tertiary age deposits, only about 55 million years old, are mostly found in North-Eastern : India in Meghalaya, Assam, Arunachal Pradesh and Nagaland.
Thus, formation of coal is a long drawn process spread over various periods.