Mining involves digging into the earth to find useful, valuable substances. The second of humankind’s earliest endeavors (after agriculture), the practice of mining for coal, gas, salt, mineral ores, gemstones, and building materials has existed for centuries.
Mining was first practiced 450,000 years ago by Paleolithic humans in the Old Stone age. Our ancestors extracted rock by chipping at it to make tools or weapons. The oldest known underground mine, located at Bomvu Ridge, Swaziland, is around 40,000 years old. Eventually, humans discovered smelting and learned to reduce the ores into pure metals.
One problem early miners faced was separating the ore from the gangue, or worthless mineral around it. Their basic tools could barely put a dent into the hard rock unless it already had cracks or crevices in it, so they could wedge or work their way to the ore. Soon, they discovered the fire setting technique: They heated the rock with fire to expand it and threw cold water on it to break it. This technique sufficed until it was replaced by a revolutionary technology developed by Alfred Nobel—dynamite.
In the past two centuries, innovations in technology have solved a lot of safety issues in mining such as lack of air or excessive water. During the nineteenth century, the invention of dynamite was the most important. In the twentieth century it was the invention of continuous mining equipment, which extracts soft minerals, like coal, without blowing them up.
Prospecting is the first stage of mining. This process searches for ores or other valuable minerals. The second stage of mining is exploration. This determines the size and value of a mineral deposit. The third stage, development, works on opening the mineral deposit to get to the ore by stripping the soil or rock covering it. Exploitation is the fourth stage which, recovers quantities of the minerals from the earth. The final stage, reclamation, is when you close the mine and restore the water on to the land and everything back to the way it was.
The precious materials collected from mines can be seen everywhere throughout daily life. From the salt you cook with to the materials that make up your cell phone, a lot of these everyday things start with mining. Without mining it would be impossible to retrieve these minerals. Mining can be a lot of work and be very dangerous but, it is valuable and helps keep the economy running.
The Kingfisher Children's Encyclopedia
Introductory Mining Engineering