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  1. en.wikipedia.org › wiki › MiningMining - Wikipedia

    Mining of sulfur from a deposit at the edge of Ijen's crater lake, Indonesia. Mining is the extraction of valuable geological materials and minerals from the surface of the Earth. Mining is required to obtain most materials that cannot be grown through agricultural processes, or feasibly created artificially in a laboratory or factory.

  2. 1 day ago · Get the latest updates on mining industry trends, projects, markets and events. Read about BHP-Anglo takeover, Peru-Kaloti dispute, Bolivia clash, deep-sea mining and more.

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    mining, process of extracting useful minerals from the surface of the Earth, including the seas. A mineral, with a few exceptions, is an inorganic substance occurring in nature that has a definite chemical composition and distinctive physical properties or molecular structure. (One organic substance, coal, is often discussed as a mineral as well.) Ore is a metalliferous mineral, or an aggregate of metalliferous minerals and gangue (associated rock of no economic value), that can be mined at a profit. Mineral deposit designates a natural occurrence of a useful mineral, while ore deposit denotes a mineral deposit of sufficient extent and concentration to invite exploitation.

    When evaluating mineral deposits, it is extremely important to keep profit in mind. The total quantity of mineral in a given deposit is referred to as the mineral inventory, but only that quantity which can be mined at a profit is termed the ore reserve. As the selling price of the mineral rises or the extraction costs fall, the proportion of the mineral inventory classified as ore increases. Obviously, the opposite is also true, and a mine may cease production because (1) the mineral is exhausted or (2) the prices have dropped or costs risen so much that what was once ore is now only mineral.

    Archaeological discoveries indicate that mining was conducted in prehistoric times. Apparently, the first mineral used was flint, which, because of its conchoidal fracturing pattern, could be broken into sharp-edged pieces that were useful as scrapers, knives, and arrowheads. During the Neolithic Period, or New Stone Age (about 8000–2000 bce), shafts up to 100 metres (330 feet) deep were sunk in soft chalk deposits in France and Britain in order to extract the flint pebbles found there. Other minerals, such as red ochre and the copper mineral malachite, were used as pigments. The oldest known underground mine in the world was sunk more than 40,000 years ago at Bomvu Ridge in the Ngwenya mountains, Swaziland, to mine ochre used in burial ceremonies and as body colouring.

    Gold was one of the first metals utilized, being mined from streambeds of sand and gravel where it occurred as a pure metal because of its chemical stability. Although chemically less stable, copper occurs in native form and was probably the second metal discovered and used. Silver was also found in a pure state and at one time was valued more highly than gold.

    According to historians, the Egyptians were mining copper on the Sinai Peninsula as long ago as 3000 bce, although some bronze (copper alloyed with tin) is dated as early as 3700 bce. Iron is dated as early as 2800 bce; Egyptian records of iron ore smelting date from 1300 bce. Found in the ancient ruins of Troy, lead was produced as early as 2500 bce.

    One of the earliest evidences of building with quarried stone was the construction (2600 bce) of the great pyramids in Egypt, the largest of which (Khufu) is 236 metres (775 feet) along the base sides and contains approximately 2.3 million blocks of two types of limestone and red granite. The limestone is believed to have been quarried from across the Nile. Blocks weighing as much as 15,000 kg (33,000 pounds) were transported long distances and elevated into place, and they show precise cutting that resulted in fine-fitting masonry.

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    Learn about the process of extracting useful minerals from the Earth, including the seas, and the history of mining from prehistoric times to modern methods. Explore the different types of mining, such as surface, underground, and hydraulic, and their effects on the environment and society.

  3. Mining is the process of generating and verifying new Bitcoin and other cryptocurrencies using specialized computers. Learn how mining works, what motivates miners, and why mining is important for the security of blockchains.

  4. NiceHash offers various ways to earn Bitcoin with your PC, GPU, CPU or ASIC miner. You can also rent or buy hashpower, join mining pools, and access the latest news and events.

  5. Oct 19, 2023 · Learn about the history, types, and impacts of mining, the process of extracting useful materials from the earth. Find out how mining can harm people and the environment with examples of diseases, pollution, and accidents.

  6. Learn about the four main mining methods: underground, open surface, placer, and in-situ mining. Find out how each method depends on the type, location, and value of the mineral resource and its environmental impact.

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