Gold mining in the context of "2000 Baia Mare cyanide spill"

Quartz reef mining is a type of gold mining in "reefs" (veins) of quartz.Quartz is one of the most common minerals in the Earth's crust, and most quartz veins do not carry gold, but those that have gold are avidly hunted by prospectors.In the shallow, oxidized zones of quartz reef deposits, the gold occurs in its metallic state, and is easily recovered with simple equipment.Quartz reef mining played an important role in 19th century gold-mining districts such as Bendigo, Victoria in Australia, Central Otago in New Zealand, and the California mother lode.

A gold nugget is a naturally occurring piece of native gold. Watercourses often concentrate nuggets and finer gold in placers. Nuggets are recovered by placer mining, but they are also found in residual deposits where the gold-bearing veins or lodes are weathered. Nuggets are also found in the tailings piles of previous mining operations, especially those left by gold mining dredges.

Amur Oblast (/əˈmʊər ˈɒblæst/) is a federal subject of Russia (an oblast), located on the banks of the Amur and Zeya rivers in the Russian Far East. The oblast borders Heilongjiang province of the People's Republic of China (PRC) to the south.

The administrative center of the oblast, the city of Blagoveshchensk, is one of the oldest settlements in the far east of the country, founded in 1856. It is a traditional center of trade and gold mining. The territory is accessed by two railways: the Trans-Siberian Railway and the Baikal–Amur Mainline. As of the 2021 Census, the oblast's population was 766,912.

The Summitville mine was a gold mining site in the United States, located in Rio Grande County, Colorado 25 miles (40 km) south of Del Norte. It is remembered for the environmental damage caused in the 1980s by the leakage of mining by-products into local waterways and then the Alamosa River.

Sodium cyanide is a compound with the formula NaCN and the structure Na C≡N. It is a white, water-soluble solid. Cyanide has a high affinity for metals, which leads to the high toxicity of this salt. Its main application, in gold mining, also exploits its high reactivity toward metals. It is a moderately strong base.

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, Venezuela, New Zealand, Brazil, Chile, South Africa, the United States, and Canada while smaller gold rushes took place elsewhere.

In the 19th century, the wealth that resulted was distributed widely because of reduced migration costs and low barriers to entry. While gold mining itself proved unprofitable for most diggers and mine owners, some people made large fortunes, and merchants and transportation facilities made large profits. The resulting increase in the world's gold supply stimulated global trade and investment. Historians have written extensively about the mass migration, trade, colonization, and environmental history associated with gold rushes.

Akmola Region is a centrally located region of Kazakhstan. It was known as Tselinograd Oblast during Soviet rule. Its capital is Kökşetau. The national capital, Astana, is enclosed by the region, but is politically separate from Aqmola Region. The region's population is 715,000; Kökşetau's is 157,000.

Some gold and coal mining occur in the area.