mining: the basics

Simple English Wikipedia is a good start:
Mining - Simple English Wikipedia, the free encyclopedia

And the Wikipedia entry itself provides a very good overview:
Mining - Wikipedia, the free encyclopedia

Diagrams are an excellent way to understand how things work:



Limestone Industry, Kentucky Geological Survey



Methods of Mining. University of Kentucky



shaft mine: types of mines -- Kids Encyclopedia | Children's Homework Help | Kids Online Dictionary | Britannica

More diagrams at:
mining diagram - Google Search

Videos are also very helpful.
Here is mining explained rather too simply, perhaps:



Minecraft: How to Mine Effectively [Diamonds, Iron, Coal etc] - YouTube

Here are some very old educational videos on gold mining in the United States:
South Dakota Saga - 1940 Gold Mining Educational Documentary - Val73TV - YouTube
Copper Mining and Smelting - 1949 Educational Documentary - Ella73TV - YouTube
mining educational - YouTube

Here's a very clear - more modern! - video on how to get gold:



How To Get Gold - YouTube

And here's another video on 'precious metals':



Gold Ore, Silver Ore and Platinum Group Metals Ore Explained - YouTube

This looks at coal:


AMERICA REVEALED | Where Does Our Coal Come From? | PBS - YouTube

Meanwhile...

The latest news is that prices for resources may be going down - but the good news for the mining industry is that new areas are being opened up:
Mining News, Mining Companies & Market Information - MINING.com
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