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Gold, a chemical element; Genomes OnLine Database; Global-scale Observations of the Limb and Disk, a NASA Explorer Mission of Opportunity; GOLD (parser), an open-source parser-generator of BNF-based grammars; Graduates of the Last Decade, an Institute of Electrical and Electronics Engineers program to garner more university level student members
Gold mining is the extraction of gold by mining. Historically, mining gold from alluvial deposits used manual separation processes, such as gold panning. The expansion of gold mining to ores that are not on the surface has led to more complex extraction processes such as pit mining and gold cyanidation. In the 20th and 21st centuries, most ...
Gold was first discovered in Montana in 1852, but mining did not begin until 1862, when gold placers were discovered at Bannack, Montana in 1862. The resulting gold rush resulted in more placer discoveries, including those at Virginia City in 1863, and at Helena and Butte in 1864. [32] In 1867, the Atlantic Cable Quartz Lode was located.
Gold-bearing magma rising after being subducted under the continental crust.. Geologic evidence indicates that over a span of at least 400 million years, gold that had been widely dispersed in the Earth's crust became more concentrated by geologic actions into the gold-bearing regions of California.
Gold has shaped global civilization since ancient times. In 4000 B.C. Eastern Europeans began creating decorative objects with it, and gold jewelry has been excavated from ancient Egyptian tombs.
A gold rush or gold fever is a discovery of gold—sometimes accompanied by other precious metals and rare-earth minerals—that brings an onrush of miners seeking their fortune. Major gold rushes took place in the 19th century in Australia , Greece , New Zealand , Brazil , Chile , South Africa , the United States , and Canada while smaller ...
However, the only Bronze Age object from Central Europe whose tin has been scientifically provenanced is the Nebra sky disk, and its tin (and gold, though not its copper), is shown by tin isotopes to have come from Cornwall. [20] In addition, a rare find of a pure tin ingot in Scandinavia was provenanced to Cornwall. [21]
The earliest gold artifacts were discovered at the site of Wadi Qana in the Levant. [13] Silver is estimated to have been discovered in Asia Minor shortly after copper and gold. [14] There is evidence that iron was known from before 5000 BC. [15] The oldest known iron objects used by humans are some beads of meteoric iron, made in Egypt in ...