Ore is natural rock or sediment that contains one or more valuable minerals concentrated above background levels, typically containing metals, that can be mined, treated and sold at a profit. The grade of ore refers to the concentration of the desired material it contains. The value of the metals or minerals a rock contains must be weighed against the cost of extraction to determine whether it is of sufficiently high grade to be worth mining and is therefore considered an ore. A complex ore is one containing more than one valuable mineral.
Placer Dome Inc. was a large mining company specializing in gold and other precious metals, with corporate headquarters in Vancouver, British Columbia, Canada.
Newmont Corporation is an American gold mining company based in Greenwood Village, Colorado. It is the world's largest gold mining corporation. Incorporated in 1921, it owns gold mines in Nevada, Colorado, Ontario, Quebec, Mexico, the Dominican Republic, Australia, Ghana, Argentina, Peru, and Suriname. In addition to gold, Newmont mines copper, silver, zinc and lead.
The Southeast Missouri Lead District, commonly called the Lead Belt, is a lead mining district in the southeastern part of Missouri. Counties in the Lead Belt include Saint Francois, Crawford, Dent, Iron, Madison, Reynolds, and Washington. This mining district is the most important and critical lead producer in the United States.
The Homestake Mine was a deep underground gold mine located in Lead, South Dakota. Until it closed in 2002 it was the largest and deepest gold mine in the Western Hemisphere. The mine produced more than forty million troy ounces of gold during its lifetime. This is about 2,500 cubic feet (71 m3) or a volume of gold roughly equal to 18,677 US gallons.
In the United States, copper mining has been a major industry since the rise of the northern Michigan copper district in the 1840s. In 2017, the US produced 1.27 million metric tonnes of copper, worth $8 billion, making it the world's fourth largest copper producer, after Chile, China, and Peru. Copper was produced from 23 mines in the US. Top copper producing states in 2014 were Arizona, Utah, New Mexico, Nevada, and Montana. Minor production also came from Idaho and Missouri. As of 2014, the US had 45 million tonnes of known remaining reserves of copper, the fifth largest known copper reserves in the world, after Chile, Australia, Peru, and Mexico.
In the United States, gold mining has taken place continually since the discovery of gold at the Reed farm in North Carolina in 1799. The first documented occurrence of gold was in Virginia in 1782. Some minor gold production took place in North Carolina as early as 1793, but created no excitement. The discovery on the Reed farm in 1799 which was identified as gold in 1802 and subsequently mined marked the first commercial production.
Ralph Jackson Roberts (1911–2007) was an American geologist and research scientist with the USGS. He is credited with the discovery of the Carlin and Battle Mountain Gold Belts, which make up the richest gold-mining region in Nevada as well as the United States.
Gold mining in Nevada, a state of the United States, is a major industry, and one of the largest sources of gold in the world. In 2018 Nevada produced 5,581,160 troy ounces, representing 78% of US gold and 5.0% of the world's production. Total gold production recorded from Nevada from 1835 to 2017 totals 205,931,000 troy ounces (6,405.2 t), worth US$322.6 billion at 2020 values. Much of Nevada's gold production comes from large open pit mining using heap leaching recovery.
John Sealy Livermore was an American geologist who discovered or helped to discover four major gold deposits in northern Nevada.
The Carlin Unconformity or Carlin Trend is a geologic feature in northeastern Nevada which represents a period of erosion or non-deposition likely associated with a collision between a tectonic crustal block called a terrane and the North American Plate. The collision occurred during the Mississippian Period, about 350 million years before present. The collision is associated with the Antler Orogeny.
Getchellite is a rare sulfide of arsenic and antimony, AsSbS3, that was discovered by B. G. Weissberg of the New Zealand Department of Scientific and Industrial Research in 1963, and approved as a new species by the International Mineralogical Association in 1965. Many metal sulfides are grey to black, but a few are brightly colored. Orpiment is yellow to brownish gold, cinnabar is deep red and getchellite is a bright orange red.
Allchar deposit is a low-temperature hydrothermal gold–arsenic–antimony–thallium deposit in Kavadarci Municipality of North Macedonia. For some time, the thallium-rich part of the deposit was mined. The Crven Dol mine yielded thallium and the ore body still holds estimated amount of 500 t of thallium. The mineral lorandite from this ore deposit can be used to determine the solar neutrino flux.
Carlin–type gold deposits are sediment-hosted disseminated gold deposits. These deposits are characterized by invisible gold in arsenic rich pyrite and arsenopyrite. This dissolved kind of gold is called "invisible gold", as it can only be found through chemical analysis. The deposit is named after the Carlin mine, the first large deposit of this type discovered in the Carlin Trend, Nevada.
Goldstrike is a gold mine in Eureka County in north-eastern Nevada. It is located on the Carlin Trend, a prolific gold mining district. It is owned and operated by Barrick Gold. Since Barrick acquired Goldstrike in 1986, until 2018 it produced 44.4 million ounces of gold.
Christite is a mineral with the chemical formula TlHgAsS3. It is named after Dr. Charles L. Christ, a member of the U.S. Geological Survey. It usually comes in a crimson red or bright orange color. It has a density of 6.2 and has a rating between 1 and 2 on Mohs Hardness Scale. Christite has an adamantine luster and leaves behind an orange streak. Its crystal system is monoclinic with possible crystal classes of twofold symmetry, mirror plane symmetry, and twofold with a mirror plane. This means it can have radial symmetry, mirror plane symmetry, or mirror plane symmetry perpendicular to the two-fold axis. It is an anisotropic mineral, which means that it exhibits different properties when measured in different directions. In plane polarized light, its color is golden yellow. It is birefringent, which means that it has two distinct indices of refraction. This can be seen when one looks through the microscope with both polars crossed and sees the mineral change colors when it is rotated.
The Mineral Park mine is a large open-pit copper mine located in the Cerbat Mountains, 14 mi (23 km) northwest of Kingman, Arizona. A 2013 report said that Mineral Park has an estimated reserves of 389 million t of ore grading 0.14% copper and 31 million oz of silver.
Nevada Gold Mines was formed on July 1, 2019, as a joint venture between Barrick Gold and Newmont through the combination of their significant gold mining assets across northern Nevada. The assets in Nevada Gold Mines include 10 underground mines and 12 surface mines as well as related facilities. Barrick Gold is the operator of Nevada Gold Mines, and plans 200 MW of Ohio made solar panels for 2023.
The epithermal vein deposit (EVP) is a type of mineral deposit that forms in the shallow subsurface, typically at depths of less than 1,500 meters below the Earth's surface. These deposits are formed by hot, mineral-rich fluids that circulate through fractures and cracks in rocks. As the fluids cool, they deposit minerals, such as gold, silver, copper, lead, and zinc, into the veins. EVP are typically small in size, but they can be very high-grade, meaning that they contain a high concentration of valuable minerals.
