The Gold Mine in The Clouds (excellent documentary to watch to understand the developmental process and challenge of mining)

Mine- At 14,000 feet, in the remote jungles of New Guinea is the largest gold and copper deposit in the world. Getting to that deposit and building a profitable mine was one of the biggest engineering challenges ever. In 1975 an American mining company took up the challenge and using the most sophisticated technology available, conquered the jungle and built the Grasberg Mine!