Mining, Past and Present
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Today we make stuff in three ways. Plants and animals make our food, wood and fiber. Oil and gas make plastic, fuels, chemicals and clothing.
And rocks, dug out of a mine, become metal, concrete and stone – which make our buildings and roads, planes, trains and automobiles, energy infrastructure and much more.
By weight and value, our most important mined product is coal – which makes about 1/3 of global electricity.
Coal was also the first thing humans mined at scale, 20,000 years ago in South Africa.
Around 6,000 years ago, we figured out how to smelt metal out of ore. Copper, gold, silver, tin and iron shaped civilizations in the Bronze and Iron ages, making weapons and tools, art and currency.
Today, we mine in several ways. Surface mines dig out shallow ore deposits or stone.
Underground mines dig tunnels to reach deeper reserves.
Placer mining separates minerals from erosion runoff.
Solution mining dissolves minerals in place with a solvent, which is then pumped to the surface and purified.
All forms of mining have environmental impacts. Surface mines can deforest large areas and disrupt ecosystems. Waste rock, and polluted water and air can impact local communities.
In another EarthDate, we talk about ways to address these impacts, as we ramp up mining to meet the demands of new technology.