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  2. Placer mining - Wikipedia

    en.wikipedia.org/wiki/Placer_mining

    Placer mining is frequently used for precious metal deposits (particularly gold) and gemstones, both of which are often found in alluvial deposits—deposits of sand and gravel in modern or ancient stream beds, or occasionally glacial deposits. The metal or gemstones, having been moved by stream flow from an original source such as a vein, are ...

  3. Environmental impact of mining - Wikipedia

    en.wikipedia.org/wiki/Environmental_impact_of_mining

    Adverse mining effects on biodiversity depend a great extent on the nature of the contaminant, the level of concentration at which it can be found in the environment, and the nature of the ecosystem itself. Some species are quite resistant to anthropogenic disturbances, while some others will completely disappear from the contaminated zone.

  4. Mercury contamination in California waterways - Wikipedia

    en.wikipedia.org/wiki/Mercury_contamination_in...

    The roots of mercury poisoning in waterways began with the historic mining of gold within California's streambed and hillsides; since the California Gold Rush, mercury has been used for gold extraction for its ability as a catalyze with the precious metal. due to the process of extraction and washing, mercury used would either be burned away as ...

  5. Fruit production and deforestation - Wikipedia

    en.wikipedia.org/wiki/Fruit_production_and...

    Mining: Mining can also lead to deforestation, as trees are cleared to access mineral resources. [ 21 ] [ 22 ] [ 23 ] Mining is the process of extracting minerals from the Earth's crust. It is a major industry in many parts of the world, and it is essential for providing raw materials for a variety of products, such as metals, minerals, and fuels.

  6. Environmental effects of placer mining - Wikipedia

    en.wikipedia.org/?title=Environmental_effects_of...

    Retrieved from "https://en.wikipedia.org/w/index.php?title=Environmental_effects_of_placer_mining&oldid=701367323"

  7. Placer deposit - Wikipedia

    en.wikipedia.org/wiki/Placer_deposit

    Placer mining is an important source of gold, and was the main technique used in the early years of many gold rushes, including the California Gold Rush. Types of placer deposits include alluvium, eluvium, beach placers, aeolian placers and paleo-placers. [2] Placer materials must be both dense and resistant to weathering processes. To ...

  8. Environmental history of Latin America - Wikipedia

    en.wikipedia.org/wiki/Environmental_history_of...

    Placer mining of gold in the Caribbean did not have a major impact on the natural environment, but it did have a devastating impact on the indigenous populations. Europeans sought indigenous labor for placer mining to the exclusion of other activities, including tending crops. The Europeans initiated slave raiding elsewhere in the Caribbean.

  9. Hydraulic mining - Wikipedia

    en.wikipedia.org/wiki/Hydraulic_mining

    Gold miners excavate an eroded bluff with jets of water at a placer mine in Dutch Flat, California sometime between 1857 and 1870.. The modern form of hydraulic mining, using jets of water directed under very high pressure through hoses and nozzles at gold-bearing upland paleogravels, was first used by Edward Matteson near Nevada City, California in 1853 during the California Gold Rush. [3]