Gold was first discovered in Minnesota in 1865, but commercially viable placer gold quantities have since eluded explorers. MORE?
Economic geology is concerned with earth materials that can be used for economic and/or industrial purposes. These materials include precious and base metals, nonmetallic minerals, construction-grade stone, petroleum minerals, coal, and water. The term commonly refers to metallic mineral deposits and mineral resources. The techniques employed by other earth science disciplines (such as geochemistry, mineralogy, geophysics, petrology and structural geology) might all be used to understand, describe, and exploit an ore deposit.
Economic geology is studied and practiced by geologists. However it is of prime interest to investment bankers, stock analysts and other professions such as engineers, environmental scientists, and conservationists because of the far-reaching impact that extractive industries have on society, the economy, and the environment.
Gold mining is the process of mining of gold or gold ores from the ground. There are several techniques and processes by which gold may be extracted from the earth.
Placer mining (// or //) is the mining of alluvial deposits for minerals. This may be done by open-pit (also called open-cast mining) or by various surface excavating equipment or tunneling equipment.
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, is typically only a minuscule portion of the total deposit. Since gems and heavy metals like gold are considerably more dense than sand, they tend to accumulate at the base of placer deposits.
Gold mining in Alaska
Surface mining, including strip mining, open-pit mining and mountaintop removal mining, is a broad category of mining in which soil and rock overlying the mineral deposit (the overburden) are removed. It is the opposite of underground mining, in which the overlying rock is left in place, and the mineral removed through shafts or tunnels.
Surface mining began in the mid-sixteenth century and is practiced throughout the world, although the majority of surface mining occurs in North America. It gained popularity throughout the 20th century, and is now the predominant form of mining in coal beds such as those in Appalachia and America's Midwest.
Gold mining in Alaska, a state of the United States, has been a major industry and impetus for exploration and settlement since a few years after the United States acquired the territory from Russia. Russian explorers discovered placer gold in the Kenai River in 1848, but no gold was produced. Gold mining started in 1870 from placers southeast of Juneau, Alaska.
Gold is found and has been mined throughout Alaska; except in the vast swamps of the Yukon Flats, and along the North Slope between the Brooks Range and the Beaufort Sea. Areas near Fairbanks, Juneau, and Nome are responsible for most of Alaska's historical and current gold production. Nearly all of the large and many of the small placer gold mines currently operating in the US are in Alaska. Six modern large-scale hard rock mines operate in Alaska in 2008; four of those are gold-producing mines (an additional gold mine suspended production in late 2007). There are also some small-scale hard rock gold-mining operations. Alaska currently produces more gold (in 2007: 673,274 troy oz from lode mines, and 53,848 troy oz from placer deposits) than any state except Nevada. In 2007, gold accounted for 15% of the mining wealth produced in Alaska. Zinc and lead, mainly from the Red Dog mine, accounted for 73%; silver, mainly from the Greens Creek mine, accounted for 8%; coal and aggregates accounted for nearly 2% each. Alaska produced a total of 40.3 million troy ounces of gold from 1880 through the end of 2007.
The term crime does not, in modern times, have any simple and universally accepted definition, but one definition is that a crime, also called an offence or a criminal offence, is an act harmful not only to some individual, but also to the community or the state (a public wrong). Such acts are forbidden and punishable by law.
Hospitality is the relationship between the guest and the host, or the act or practice of being hospitable. This includes the reception and entertainment of guests, visitors, or strangers.