123-588: Empire Mine State Historic Park is a state-protected mine and park in the Sierra Nevada mountains in Grass Valley , California , U.S. The Empire Mine is on the National Register of Historic Places , a federal Historic District , and a California Historical Landmark . Since 1975 California State Parks has administered and maintained the mine as a historic site. The Empire Mine is "one of
246-711: A combination of factors including the depletion of easily accessible gold deposits, harsh weather conditions, and the political instability at the time. The Welsh gold rush occurred in Wales , more so in the Dolgellau area of Gwynedd , during the 19th century. Gold deposits were discovered in Welsh mountains, with reports of gold being found in rivers Mawddach and Tryweryn . By the mid-19th century, commercial mining operations had begun. Wales' gold gained popularity for its quality and rarity, leading to its use in royal jewelry for
369-722: A critical source of income and livelihood, providing employment opportunities and economic support in regions with limited alternative options. Artisanal mining operations vary in scale, from individuals panning for gold in rivers and streams, to small groups working collectibely in informal mining camps, often referred to as ' galamsey ' in West Africa . Gold mining can create employment opportunities in mining operations and related sectors. Howevers, these jobs may be temporary. The sector's reliance on fluctuating global gold prices can lead to economic stability for communities dependent on mining. The discovery of significant gold deposits in
492-755: A cyanide plant in 1910, which was an easier gold recovery process than chlorination . In 1915, Bourn acquired the Pennsylvania Mining Co., and the Work Your Own Diggings Co., neighboring mines, which gave the Empire Mines and Investment Co. access to the Pennsylvania vein. The North Star also had some rights to that vein, but both companies compromised and made an adjustment. In 1928, at the recommendation of Fred Searls of Nevada City , Newmont Mining Corp. purchased
615-532: A foreman working for Sacramento pioneer John Sutter , found shiny metal in the tailrace of a lumber mill Marshall was building for Sutter on the American River . Rumors soon started to spread and were confirmed in March 1848 by San Francisco newspaper publisher and merchant Samuel Brannan . Brannan strode through the streets of San Francisco, holding aloft a vial of gold, shouting "Gold! Gold! Gold from
738-437: A gravel screening plant and sluice box floating in a temporary pond. The pond is excavated in the gravel bar and filled from the natural water table. "Pay" gravel is excavated from the front face of the pond and processed through the floating plant, with the gold trapped in the onboard sluice box and tailings stacked behind the plant, steadily filling in the back of the pond as the operation moves forward. This type of gold mining
861-471: A large scale to extract gold from extensive alluvial (loose sediment) deposits, such as those at Las Medulas . Mining was under the control of the state but the mines may have been leased to civilian contractors some time later. The gold served as the primary medium of exchange within the empire, and was an important motive in the Roman conquest of Britain by Claudius in the first century AD; although there
984-488: A lower grade. Tailings can contain lead, mercury, cadmium, and arsenic. These toxins can pose health risks for local communities. Arsenic is typically found in gold-containing ores, and gold processing may contaminate groundwater or the atmosphere. This pollution may persist for decades. Furthermore, mining operations use large quantities of water for processing ore and can result in the contamination of water sources with heavy metals, such as mercury and cyanide , used in
1107-571: A portion of the area, a triangle whose vertices are Reno, Nevada ; Fresno, California ; and Las Vegas, Nevada , has been dubbed the " Nevada Triangle ", in reference to the Bermuda Triangle . Some counts put the number of crashes in the triangle at 2,000, including millionaire and record-breaking flyer Steve Fossett . Hypotheses that the crashes are related in some way to the United States Air Force 's Area 51 , or to
1230-448: A powerful stream or jet of water at gold-bearing gravel beds. It is estimated that by the mid-1880s, 11 million troy ounces (340 metric tons) of gold (worth approximately US$ 16 billion in 2020 prices) had been recovered by "hydraulicking". A consequence of these extraction methods was that large amounts of gravel, silt , heavy metals , and other pollutants were washed into streams and rivers. As of 1999 , many areas still bear
1353-706: A publication of his photographs under the title Parmelian Prints of the High Sierras , commented, "The name Sierra is already a plural. To add an s is a linguistic, Californian, and mountaineering sin." The Sierra Nevada lies primarily in Central and Eastern California , with the Carson Range , a small but historically important spur, extending into Nevada. West-to-east, the Sierra Nevada's elevation increases gradually from 500 feet (150 m) in
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#17327796754261476-501: A short period, and the lightning can start fires. Summer high temperatures average 42–90 °F (6–32 °C). Winters are comparatively mild, and the temperature is usually only just low enough to sustain a heavy snowpack. For example, Tuolumne Meadows , at 8,600 feet (2,600 m) elevation, has winter daily highs about 40 °F (4 °C) with daily lows about 10 °F (−12 °C). The growing season lasts 20 to 230 days, strongly dependent on elevation. The highest elevations of
1599-617: A state historic park. The state park now contains 853 acres (345 ha; 3.45 km; 1.333 sq mi), including forested backcountry. Newmont Mining retained the mineral rights to the Empire Mine, and 47 acres, if they decide to reopen the Empire Star Mines. A Granodiorite body five miles (8 km) long, north to south, and up to two miles (3.2 km) wide, underlies the district. This body intruded into surrounding metamorphic rocks . Gold ore deposits reside in
1722-747: A tributary of the Klondike River by George Carmack and his Indigenous companions, Skookum Jim Mason and Tagish Charlie . As prospectors arrived in Klondike, makeshift towns and settlements sprang up along the rivers, including Dawson City , which because the largest town in Yukon at the height of the gold rush. Prospectors employed various mining techniques to extract gold from the Klondike's streams and riverbeds, including placer mining, dredging, and hydraulic mining. The Carlin Trend of Nevada, U.S.,
1845-447: Is Mount Lyell (13,120 ft or 3,999 m). The Sierra rises to almost 14,000 feet (4,300 m) with Mount Humphreys near Bishop, California . Finally, near Lone Pine , Mount Whitney is at 14,505 feet (4,421 m), the highest point in the contiguous United States . South of Mount Whitney, the elevation of the range quickly dwindles. The crest elevation is almost 10,000 feet (3,000 m) near Lake Isabella , but south of
1968-418: Is a cyanide extraction method, or gold cyanidation, introduced in the late 1800s. This a metallurgical technique used to extract gold from lower grade ores by converting gold into a water-soluble coordination complex. Finely ground rock is treated with a solution of sodium cyanide . The extract is absorbed onto carbon and then removed from the carbon with a solution of caustic soda and cyanide. Gold cyanide
2091-429: Is a method of extracting gold from alluvial deposits such as sand, gravel, and sediment. These are known as placer deposits which are typically found in riverbeds, stream beds, and floodplains. These deposits typically contain minerals that are resistant to weathering and eroision like gold , platinum , diamonds , and more. They are characterized by their relatively high concentration of valuable minerals compared to
2214-415: Is characterized by its low cost, as each rock is moved only once. It also has low environmental impact, as no stripping of vegetation or overburden is necessary, and all process water is fully recycled. Such operations are typical on New Zealand's South Island and in the Klondike region of Canada. Also called a cradle, a rocker box uses riffles located in a high-walled box to trap gold in a similar manner to
2337-616: Is done by small-scale miners using suction dredges. These are small machines that float on the water and are usually operated by one or two people. A suction dredge consists of a sluice box supported by pontoons, attached to a suction hose which is controlled by a miner working beneath the water. This method is particularly popular in areas where gold is found at river bottoms or submerge deposits . Suction dredging can have environmental impacts, moreso on aquatic habitats and water quality. Regulations and best practices are often in place to minimize these impacts. State dredging permits in many of
2460-456: Is either protected from development or strictly managed. The mountain range is home to three National Parks – Yosemite , Kings Canyon , and Sequoia – and two national monuments – Devils Postpile and Giant Sequoia . Ten national forests span much of the mountain range's remaining area. Within these national parks, monuments, and forests lie 26 wilderness areas , which together protect 15.4% of
2583-436: Is essentially a man made channel with riffles set in the bottom. The riffles are designed to create dead zones in the current to allow gold to drop out of suspension. The box is placed in the stream to channel water flow. Gold-bearing material is placed at the top of the box. The material is carried by the current through the volt where gold and other dense material settles out behind the riffles. Less dense material flows out of
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#17327796754262706-868: Is estimated that the total gold production in Karnataka to date is 1000 tons. The mining of the Hungarian deposit (present-day Slovakia) primarily around Kremnica was the largest of the Medieval period in Europe. In South America, gold mining in the Andes dates back to thousands of years, with the Inca empire employing extensive gold mining operations in regions such as present-day Peru and Ecuador . They used stone tools and simple mining techniques to extract gold from rivers, streams, and surface deposits. During
2829-542: Is higher in the east. A list of biotic zones, and corresponding elevations, is presented below: Archaeological excavations placed Martis people of Paleo-Indians in northcentral Sierra Nevada during the period of 3,000 BCE to 500 CE. The earliest identified sustaining indigenous people in the Sierra Nevada were the Northern Paiute tribes on the east side, with the Mono tribe and Sierra Miwok tribe on
2952-698: Is only one known Roman gold mine at Dolaucothi in west Wales. Gold was a prime motivation for the campaign in Dacia when the Romans invaded Transylvania in what is now modern Romania in the second century AD. The legions were led by the emperor Trajan, and their exploits are shown on Trajan's Column in Rome and the several reproductions of the column elsewhere (such as the Victoria and Albert Museum in London ). Under
3075-966: Is produced by major corporations, there are an estimated 10 to 15 million small-scale artisanal gold miners worldwide. Around 4.5 million of them are women, and an estimated 600,000 children work in illegal artisanal gold mines. Artisanal miners use rudimentary methods to extract and process gold. Many of these people are mining to escape extreme poverty , unemployment and landlessness . In Ghana, galamsey miners are estimated to number 20,000 to 50,000. In neighboring francophone countries, such workers are called orpailleurs . In Brazil, Venezuela, Suriname, and French Guiana, workers are called garimpeiros . These workers are not required to claim responsibility for their social and environmental impacts. Miners risk government persecution, mine shaft collapses, and toxic poisoning from unsafe chemicals used in processing, such as mercury. For example, in Ghana during 2009,
3198-709: Is the source of much of the sedimentary rock in California. In the Cretaceous , a subduction zone formed at the edge of the continent. This means that an oceanic plate started to dive beneath the North American Plate . Magma, formed through the subduction of the ancient Farallon Plate , rose in plumes ( plutons ) deep underground, their combined mass forming what is called the Sierra Nevada batholith . These plutons formed at various times, from 115 Ma to 87 Ma. The earlier plutons formed in
3321-633: Is then converted to relatively pure gold through gold parting . There are many environmental hazards associated with this extraction method, largely due to the high toxicity of the cyanide compounds. Furthermore, there are potentials for accidental spills or leaks to cause harm to aquatic ecosystems and human health. For example, in 2000, the Baia Mare cyanide spill in northern Romania released approximately 100,000 cubic metres (3,500,000 cu ft) of waste water contaminated with heavy metal sludge and up to 120 long tons (122 t) of cyanide into
3444-532: Is unknown, but some of the oldest known gold artifacts were found in the Varna Necropolis in Bulgaria . The graves of the necropolis were built between 4700 and 4200 BC, indicating that gold mining could be at least 6,724 years old. During a series of excavations carried out between 1878 and 1992, several graves were found with more than 6kg of gold. A group of German and Georgian archaeologists claims
3567-462: The Basin and Range Province . As this andesitic volcanism began waning about five million years ago, the rivers were able to begin eroding away the 100s of meters of volcanic deposits and resume the incision that had been halted by the first period of volcanism. Some studies have argued that this recent incision is a sign of recent tectonic uplift. Other geologists claim that the elevations of many of
3690-576: The British royal family . During the 19th century, numerous gold rushes in remote regions around the globe caused large migrations of miners, such as the California Gold Rush of 1849. This is one of the most famous gold rushes in history. The discovery of gold at Sutter's Mill in California sparked a massive migration of people from around the world to California in search of gold. The rush significantly accelerated westward expansion in
3813-722: The Bronze Age , sites in the Eastern Desert became a great source of gold-mining for nomadic Nubians, who used "two-hand-mallets" and "grinding ore extraction ." By the Old Kingdom , the oval mallet was introduced for mining. By the Middle Kingdom , stone mortars to process ores and a new gold-washing technique were introduced. During the New Kingdom , Nubian mining expanded under Egyptian occupation with
Empire Mine State Historic Park - Misplaced Pages Continue
3936-661: The Carson River runs into Carson Sink , the Walker River into Walker Lake ; Rush , Lee Vining and Mill Creeks flow into Mono Lake ; and the Owens River into dry Owens Lake . Although none of the eastern rivers reach the sea, many of the streams from Mono Lake southwards are diverted into the Los Angeles Aqueduct which provides water to Southern California . The height of the mountains in
4059-550: The Central Valley to more than 14,000 feet (4,300 m) atop the highest peaks of its crest 50 to 75 miles (80 to 121 km) to the east. The east slope forms the steep Sierra Escarpment . Unlike its surroundings, the range receives a substantial amount of snowfall and precipitation due to orographic lift . The Sierra Nevada's irregular northern boundary stretches from the Susan River and Fredonyer Pass to
4182-578: The Dompoase mine collapse killed 18 workers. It was the worst mining disaster in Ghanaian history. Children in these mines suffer extremely harsh working conditions and various hazards such as collapsing tunnels, explosions, and chemical exposure. Children may be especially vulnerable to these hazards and many suffer from serious respiratory conditions, hearing, and vision problems. Gold mining by large multi-national corporations produces about 80% of
4305-733: The Great Basin . The vast majority of the range lies in the state of California , although the Carson Range spur lies primarily in Nevada . The Sierra Nevada is part of the American Cordillera , an almost continuous chain of mountain ranges that forms the western "backbone" of the Americas. The Sierra runs 400 mi (640 km) north-south, and its width ranges from 50 mi (80 km) to 80 mi (130 km) across east–west. Notable features include General Sherman ,
4428-690: The Kolar gold fields was mined to a depth of 50 metres (160 ft) during the Gupta period in the fifth century AD. During the Chola period in the 9th and 10th century AD, the scale of the operation grew. The metal continued to be mined by the eleventh century kings of South India, the Vijayanagara Empire from 1336 to 1560, and later by Tipu Sultan , the king of Mysore state and the British. It
4551-595: The Nevadan orogeny , granite formed deep underground. The range started to uplift less than five million years ago, and erosion by glaciers exposed the granite and formed the light-colored mountains and cliffs that make up the range. The uplift caused a wide range of elevations and climates in the Sierra Nevada, which are reflected by the presence of five life zones (areas with similar plant and animal communities). Uplift continues due to faulting caused by tectonic forces, creating spectacular fault block escarpments along
4674-611: The North Fork Feather River . It represents where the granitic bedrock of the Sierra Nevada dives below the southern extent of Cenozoic igneous surface rock from the Cascade Range . It is bounded on the west by California 's Central Valley , on the east by the Basin and Range Province , and on the southeast by the Mojave Desert . The southern boundary is at Tehachapi Pass . Physiographically,
4797-462: The Sakdrisi site in southern Georgia , dating to the 3rd or 4th millennium BC, may be the world's oldest known gold mine. Gold has been prized by humans since prehistoric times. Archaeological evidence suggests that humans were mining gold as far back as 4000 BCE, with some the earliest known gold artifacts dating back to ancient Mesopotamia . Particularly in the region of present-day Iraq, gold
4920-529: The San Joaquin Valley to the rest of the state in the 1870s. This facilitated the nationwide distribution of lumber. In addition, technological advancements, such as the shay locomotive and the v-shaped log flume , made it easier to transport lumber across mountainous terrain. The tourism potential of the Sierra Nevada was recognized early in the European history of the range. Yosemite Valley
5043-517: The Tisza River. Historically, mercury was used extensively in placer gold mining in order to form mercury-gold amalgam with smaller gold particles, and thereby increase the gold recovery rates. First, the gold ore is crushed and ground to a fine powder to expose the gold particles for amalgamation. Then, this finely ground ore is mixed with liquid mercury to amalgamate it. Mercury forms an amalgam, an alloy, with gold particles to allow for
Empire Mine State Historic Park - Misplaced Pages Continue
5166-537: The United States started to move to California via Sonora and Walker Passes . In the winter of 1844, Lt. John C. Frémont , accompanied by Kit Carson , was the first European American to see Lake Tahoe . The Frémont party camped at 8,050 ft (2,450 m). The California Gold Rush began at Sutter's Mill , near Coloma , in the western foothills of the Sierra. On January 24, 1848, James W. Marshall,
5289-524: The endorheic basin of Tulare Lake , which rarely overflows into the San Joaquin during wet years. The eastern slope watershed of the Sierra is much narrower; its rivers flow out into the endorheic Great Basin of eastern California and western Nevada . From north to south, the Susan River flows into intermittent Honey Lake , the Truckee River flows from Lake Tahoe into Pyramid Lake ,
5412-503: The quartz veins , ranging from 3 to 7 ounces per ton. The Empire Vein outcrops to the east on a north–south strike , dipping at a 35-degree angle to the west. The vein was mined with inclined shafts following dip, with horizontal shafts (drifts) every 300–400 ft (90–120 m) along strike. The ore was mined by stoping . On weekends from May through October, volunteers dressed in Edwardian clothing give living history tours of
5535-574: The Amazon rainforest, Indigenous peoples have been killed and had their rightfully owned land stolen from them. As a consequence of this, some have left the rainforest to move to cities which further puts them at risk to disease, homelessness, and poverty. Artisanal gold mining is widespread across Africa , occurring in numerous countries including Ghana , Mali , Burkina Faso , Tanzania , Zimbabwe , and many others. For many individuals and communities in rural Africa, artisanal gold mining represents
5658-742: The American River!" On August 19, 1848, the New York Herald was the first major newspaper on the East Coast to report the discovery of gold. On December 5, 1848, President James Polk confirmed the discovery of gold in an address to Congress . Soon, waves of immigrants from around the world, later called the "forty-niners", invaded the Gold Country of California or "Mother Lode". Miners lived in tents, wood shanties, or deck cabins removed from abandoned ships. Wherever gold
5781-611: The Bourn Cottage, the 1890s country estate home of William Bourn Jr., and the Mineyard, with demonstrations of mine operations. The park's museum contains a scale model of the underground workings of the Empire/Star mine complex, exhibits of ore samples from local mines, a recreated Assay Office and a collection of minerals. There are 13 acres (5.3 ha) of gardens to tour. The Sierra Gold Park Foundation (SGPF) provides
5904-918: The Eastern Roman Empire Emperor Justinian's rule, gold was mined in the Balkans, Anatolia, Armenia, Egypt, and Nubia. In the area of the Kolar Gold Fields in Bangarpet Taluk , Kolar district of Karnataka state, India; gold was first mined prior to the 2nd and 3rd century AD by digging small pits. Golden objects found in Harappa and Mohenjo-daro have been traced to Kolar through the analysis of impurities – the impurities include 11% silver concentration, found only in KGF ore. The Champion reef at
6027-677: The Empire Mine from Bourn. Newmont also purchased the North Star Mine , resulting in Empire-Star Mines, Ltd. The business was managed by Fred Nobs and later by Jack Mann. Gold mines were defined as "nonessential industry to the war effort" by the War Production Board of the US Government on 8 October 1942, which shut down operations until 30 June 1945. After the war, a shortage of skilled miners forced
6150-432: The Empire a year later. Bourn reacquired control of the Empire Mine in 1896, forming the Empire Mines and Investment Co. In 1897, he commissioned Willis Polk to design the "Cottage", using waste rock from the mine. The "Cottage" included a greenhouse, gardens, fountains and a reflecting pool. Between 1898 and 1905, a clubhouse with tennis courts, bowling alley and squash courts were built nearby. The Empire Mine installed
6273-412: The Highlands during the 16th and 17th century. Gold deposits were discovered in rivers and streams, leading to a surge in prospecting and mining activity. The Scottish Crown took an interest in gold discoveries, in hopes of aiding the kingdom's economy and revenue. King James IV of Scotland established a royal mint to produce gold coins from Scottish gold. The Scottish gold rush eventually waned due to
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#17327796754266396-722: The Middle Ages, Europe experience several gold rushes. Most notably in regions like Transylvania, Scotland, and Wales. These rushes were often small-scale and localised compared to later rushes in history. The Transylvania gold rush took place in the Kingdom of Hungary (present-day Romania ), primarily in the region of Transylvania during the medieval period. Transylvania was known for its rich mineral resources including gold, silver, and other metals. Miners in Transylvania used both surface and underground mining techniques to extract gold from alluvial deposits and veins. These methods include panning, sluicing, and rudimentary shaft mining. The Scottish gold rush occurred in Scotland, primarily in
6519-476: The Ophir Hill Mine, but they mismanaged their finances and in 1852 were forced to sell the business at auction. It was purchased by John P. Rush and the Empire Quartz Hill Co. The Empire Mining Co. was incorporated in 1854, after John Rush was bought out. As word spread that hard rock gold had been found in California, miners from the tin and copper mines of Cornwall , England, arrived to share their experience and expertise in hard rock mining . Particularly important
6642-441: The Ophir vein after it was bottomed out at 1,200 feet (370 m) and allowed to fill with water. With his financial backing, and after 1887, the mining knowledge and management of his younger cousin George W. Starr, the Empire Mine became famous for its mining technology. Bourn purchased the North Star Mine in 1884, turning it into a major producer, and then sold it to James Duncan Hague in 1887, along with controlling interest in
6765-449: The Pacific Ocean at San Francisco . The northern third of the western Sierra is part of the Sacramento River watershed (including the Feather , Yuba , and American River tributaries), and the middle third is drained by the San Joaquin River (including the Mokelumne , Stanislaus , Tuolumne , and Merced River tributaries). The southern third of the range is drained by the Kings , Kaweah , Tule , and Kern rivers, which flow into
6888-438: The Park in 1906. In the same year, Sequoia National Park was formed to protect the Giant Sequoia: all logging of the Sequoia ceased at that time. In 1903, the city of San Francisco proposed building a hydroelectric dam to flood Hetch Hetchy Valley . The city and the Sierra Club argued over the dam for 10 years, until the U.S. Congress passed the Raker Act in 1913 and allowed dam building to proceed. O'Shaughnessy Dam
7011-403: The Sierra Nevada increases gradually from north to south. Between Fredonyer Pass and Lake Tahoe, the peaks range from 5,000 feet (1,500 m) to more than 9,000 feet (2,700 m). The crest near Lake Tahoe is roughly 9,000 feet (2,700 m) high, with several peaks approaching the height of Freel Peak (10,881 ft or 3,317 m). Farther south, the highest peak in Yosemite National Park
7134-497: The Sierra Nevada is influenced by the Mediterranean climate of California. During the fall, winter and spring, precipitation in the Sierra ranges from 20 to 80 in (510 to 2,030 mm) where it occurs mostly as snow above 6,000 ft (1,800 m). Precipitation is highest on the central and northern portions of the western slope between 5,000 and 8,000 feet (1,500 and 2,400 m) elevation, due to orographic lift . Above 8,000 feet (2,400 m), precipitation diminishes on
7257-436: The Sierra Nevada started in the early 1800s, when settlers relied on hand tools and ox-teams. Before the California Gold Rush, the industry was relatively small, and most of the lumber used in the state was imported. However, as the demand for lumber to support the mining industry increased, logging became a major industry in the region. Initially, most of the lumber produced in California was used in mining. The Comstock Lode
7380-431: The Sierra have an alpine climate . The Sierra Nevada snowpack is the major source of water and a significant source of electric power generation in California. Many reservoirs were constructed in the canyons of the Sierra throughout the 20th century, Several major aqueducts serving both agriculture and urban areas distribute Sierra water throughout the state. However, the Sierra casts a rain shadow , which greatly affects
7503-424: The Sierra is a section of the Cascade–Sierra Mountains province, which in turn is part of the larger Pacific Mountain System physiographic division. The California Geological Survey states that "the northern Sierra boundary is marked where bedrock disappears under the Cenozoic volcanic cover of the Cascade Range." The range is drained on its western slope by the Central Valley watershed, which discharges into
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#17327796754267626-445: The Sierra's 63,118 km (24,370 sq mi) from logging and grazing. The United States Forest Service and the Bureau of Land Management currently control 52% of the land in the Sierra Nevada. Logging and grazing are generally allowed on land controlled by these agencies, under federal regulations that balance recreation and development on the land. The California Bighorn Sheep Zoological Area near Mount Williamson in
7749-424: The Sierra. The combination of river and glacier erosion exposed the uppermost portions of the plutons emplaced millions of years before, leaving only a remnant of metamorphic rock on top of some Sierra peaks. Extension of the Basin and Range continues today, leading to downdropping of crustal blocks just east of the Sierra Nevada during large earthquakes, such as the Lone Pine earthquake of 1872. The climate of
7872-425: The Tuolumne and Merced River drainage. The group may have been the first non-indigenous people to see Yosemite Valley . The Walker Party probably visited either the Tuolumne or Merced Groves of giant sequoia , becoming the first non-indigenous people to see the giant trees, but journals relating to the Walker party were destroyed in 1839, in a print shop fire in Philadelphia. Starting in 1841, emigrants from
7995-410: The United States and had profound effects on the region's economy and society. The gold rushes began in 1851 when Edward Hargraves , a prospector, discovered gold near Bathhurst , New South Wales . The most well known gold rush in Australia was the Victorian Gold Rush . Thousands of people, known as 'diggers', came from around the world to Australia in search of gold, which ultimately contributed to
8118-484: The United States gold dredging areas specify a seasonal time period and area closures to avoid conflicts between dredgers and the spawning time of fish populations. Some US states, such as Montana, require an extensive permitting procedure, including permits. Some large suction dredges [100 horsepower (75 kW) & 250 mm (10 in)] are used in commercial production throughout the world. Small suction dredges are much more efficient at extracting smaller gold than
8241-444: The activities of extra-terrestrial aliens , have no evidence to support them. The Sierra Nevada is divided into a number of biotic zones , each of which is defined by its climate and supports a number of interdependent species. Life in the higher elevation zones adapted to colder weather, and to most of the precipitation falling as snow. The rain shadow of the Sierra causes the eastern slope to be warmer and drier: each life zone
8364-399: The area around Yosemite National Park and what would become Kings Canyon National Park . James S. Hutchinson , a noted mountaineer, climbed the Palisades (1904) and Mount Humphreys (1905). By 1912, the USGS published a set of maps of the Sierra Nevada, and the era of exploration was over. Logging in the Sierra Nevada has significantly impacted the landscape. The logging industry in
8487-580: The box as tailings . Larger commercial placer mining operations employ screening plants, or trommels , to remove the larger alluvial materials such as boulders and gravel, before concentrating the remainder in a sluice box or jig plant. After the gold is sorted through trommels, it is then placed through regular sluice boxes for further sorting. These operations typically include diesel powered, earth moving equipment including excavators, bulldozers, wheel loaders , and rock trucks. Although this method has largely been replaced by modern methods, some dredging
8610-407: The bulk of the labor force from the late 1870s until the mine's closure eighty years later. William Bowers Bourn acquired control of the company in 1869. Bourn died in 1874, and his estate ran the mine, abandoning the Ophir vein for the Rich Hill in 1878. Bourn's son, William Bowers Bourn II , formed the Original Empire Co. in 1878, took over the assets of the Empire Mining Co., and continued work on
8733-405: The climate and ecology of the central Great Basin . This rain shadow is largely responsible for Nevada being the driest state in the United States. Precipitation varies substantially from year to year. It is not uncommon for some years to receive precipitation totals far above or below normal. The height of the range and the steepness of the Sierra Escarpment, particularly at the southern end of
8856-656: The crest and north of 37.2°N. In the Triassic and into the Jurassic , an island arc collided with the west coast of North America and raised a chain of volcanoes, in an event called the Nevadan orogeny . Nearly all subaerial Sierran Arc volcanoes have since disappeared; their remains were redeposited during the Great Valley Sequence and the subsequent Cenozoic filling of the Great Valley, which
8979-470: The eastern edge of the southern Sierra. The Sierra Nevada has played an important role in the history of California and the United States. The California gold rush occurred in the western foothills from 1848 through 1855. Due to its inaccessibility, the range was not fully explored until 1912. Used in 1542 by Juan Rodríguez Cabrillo to describe a Pacific Coast Range ( Santa Cruz Mountains ),
9102-432: The efficient capture of gold from the ore. The gold is concentrated by boiling away the mercury from the amalgam . This process is called retorting. This is effective in extracting very small gold particles, but the process is hazardous due to the toxicity of mercury vapour. Large-scale use of mercury stopped in the 1960s. However, mercury is still used in artisanal and small-scale gold mining (ASGM). While most gold
9225-762: The extraction process. This pollution can have detrimental effects on aquatic ecosystems and human health. Soil degradation has also been found to be impacted by gold mining. Mining activities can disturb soil structure, leading to erosion, sedimentation of waterways, and loss of fertile land for agriculture or vegetation regrowth. More evidently, dust and emissions from mining machiner and processing facilities can contribute to air pollution, impacting air quality and potentially causings respiratory problems for nearby communities. Large-scale gold mining projects may require land acquisition and resettlement of local communities, leading to displacement, loss of livelihoods, and disruption of traditional ways of life. In addition to
9348-694: The gold supply. Most gold is mined in developing nations. Large mining companies play a key role in globalisation of the economy by linking rich and poor companies. Newmont and Barrick Gold are the largest gold mining companies in the world, but there are many smaller corporations in the industry. Local communities are frequently vulnerable to environmental degradation caused by large mining companies and may lack government protection or industry regulation. For example, thousands of people around Lega Dembi mine are exposed to mercury, arsenic, and other toxins resulting in widespread health problems and birth defects. Vulnerable communities may also lose their land to
9471-567: The growth of cities like Melbourne and Sydney . The discovery of gold in the Witwatersrand led to the Second Boer War and ultimately the founding of South Africa. This transformed the region into one of the wealthiest gold-producing areas in the world. This rush played a crucial role in the development of South Africa's economy and lead to the establishment of Johannesburg, known as the 'city of gold'. Gold-bearing reefs in
9594-765: The heat is unbearable for humans, and air conditioning is required for the safety of the workers. The first such mine to receive air conditioning was Robinson Deep , at that time the deepest mine in the world for any mineral. Gold is also produced by mining in which it is not the principal product. Large copper mines, such as the Bingham Canyon mine in Utah, often recover considerable amounts of gold and other metals along with copper. Sand and gravel pits, like those in Denver (Colorado), may recover small amounts of gold in their wash operations. The largest producing gold mine in
9717-465: The highest peak in the range. In 1873, Mount Whitney was climbed for the first time by 3 men from Lone Pine, California, on a fishing trip. From 1892 to 1897 Theodore Solomons made the first attempt to map a route along the crest of the Sierra. Other people finished exploring and mapping the Sierra. Bolton Coit Brown explored the Kings River watershed in 1895–1899. Joseph N. LeConte mapped
9840-509: The interpretive and educational goals of this state historic park through donations, visitor center sales, membership dues and special events. It has a very active volunteer group. Sierra Nevada (U.S.) The Sierra Nevada ( / s i ˌ ɛr ə n ɪ ˈ v æ d ə , - ˈ v ɑː d -/ see- ERR -ə nih- VA(H)D -ə ) is a mountain range in the Western United States , between the Central Valley of California and
9963-595: The invention of the grinding mill . Additionally, gold was associated with the sun god Ra and was believed to be eternal and indestructible, symbolising the pharoah's divine power and afterlife. Gold has also been found in the tombs of Tutankhamun and other pharoahs. During the Bronze Age, gold objects were also plentiful; especially in Ireland and Spain. Romans employed slave labour and used hydraulic mining methods, such as hushing and ground sluicing on
10086-522: The lake, the peaks reach only a modest 8,000 feet (2,400 m). There are several notable geographical features in the Sierra Nevada: Communities in the Sierra Nevada include Paradise , South Lake Tahoe , Truckee , Grass Valley , Lee Vining , Mammoth Lakes , Sonora , Nevada City , Placerville , Pollock Pines , Portola , Auburn , Colfax and Kennedy Meadows . Much of the Sierra Nevada consists of federal lands and
10209-683: The largest tree in the world by volume; Lake Tahoe , the largest alpine lake in North America; Mount Whitney at 14,505 ft (4,421 m), the highest point in the contiguous United States ; and Yosemite Valley sculpted by glaciers from one-hundred-million-year-old granite , containing high waterfalls . The Sierra is home to three national parks , twenty-six wilderness areas, ten national forests, and two national monuments. These areas include Yosemite , Sequoia , and Kings Canyon National Parks , as well as Devils Postpile National Monument . More than one hundred million years ago during
10332-495: The late 1800s due to several factors. The Timber and Stone Act of 1878 allowed individuals to claim ownership of old-growth timber tracts, which were later consolidated under joint-stock companies , such as those founded by Midwestern lumber magnates. These companies had the financial resources to transport timber from remote locations and build sawmills near the tracks of the Southern Pacific railroad which connected
10455-455: The late 1800s, the logging industry moved westward due to the depletion of white pine forests in the upper Midwest. This shift was encouraged by the positive portrayal of the Sierra Nevada as a promising timber region. In 1859, Horace Greely marveled, "I never saw anything so much like good timber in the course of any seventy-five miles' travel as I saw in crossing the Sierra Nevada." The logging industry experienced significant growth in
10578-461: The lowest ever recorded for tropical forests, with there being little to no tree regeneration at abandoned mining camps, even after several years. The Amazon rainforest is at risk for 'savannization', which is the gradual transformation of a tropical rainforest into a savannah. This would ultimately lead to a collapse of biodiversity, ecosystems, and climate. Gold mining produces more waste than mining of other minerals, because it can be mined at
10701-663: The mine. Some large companies have attempted to build local legitimacy through corporate responsibility initiatives and local development. Gold mining can significantly alter the natural environment. Gold mining activities in tropical forests are increasingly causing deforestation along rivers and in remote areas rich in biodiversity. Mining has increased rainforest loss up to 70km beyond lease boundaries, causing nearly 11,670 km of deforestation between 2005 to 2015. Up to 9% of gold mining occurs outside of these regulated lease boundaries. Other gold mining impacts, particularly in aquatic systems with residual cyanide or mercury (used in
10824-499: The miners, provoking counter-attacks on native villages. The Native Americans, out-gunned, were often slaughtered. The Gold Rush populated the western foothills of the Sierra Nevada, but even by 1860, most of the Sierra was unexplored. The state legislature authorized the California Geological Survey to officially explore the Sierra (and survey the rest of the state). Josiah Whitney was appointed to head
10947-492: The modern rivers flowing down the range are only 100–300 meters (300–1,000 ft) lower than their ancient counterparts from 30–40 million years ago and the overall elevation and bedrock topography of the northern Sierra Nevada has changed little since at least 30–40 million years ago. About 2.5 Ma, the Earth's climate cooled, and ice ages started. Glaciers carved out characteristic U-shaped canyons throughout
11070-712: The mountains were amongst a group led by fur trapper Jedediah Smith , crossing north of the Yosemite area in May 1827, at Ebbetts Pass . In 1833, a subgroup of the Bonneville Expedition led by Joseph Reddeford Walker was sent westward to find an overland route to California . Eventually the party discovered a route along the Humboldt River across present-day Nevada , ascending the Sierra Nevada, starting near present-day Bridgeport and descending between
11193-409: The mountains. Washo and Maidu were also in this area prior to the era of European exploration and displacement. American exploration of the mountain range started in 1827. Although prior to the 1820s there were Spanish missions , pueblos (towns), presidios (forts), and ranchos along the coast of California, no Spanish explorers visited the Sierra Nevada. The first Americans to visit
11316-744: The neighbouring Free State province were found shortly thereafter, driving significant development in the region with the establishment of the Free State goldfields . Also known as the Yukon Gold Rush , brought prospectors from around the world to the Klondike region of the Yukon territory in Canada . The Klondike Gold Rush began in 1896, when gold was discovered in Bonanza Creek ,
11439-399: The northern Sierran valleys with volcanic deposits. These pyroclastic flows, which continued for about 10 million years, were followed by andesitic lahars which nearly completely buried the northern Sierran landscape such that only the tallest peaks emerged above a volcanic plain. This second period of volcanism appears to have been triggered by crustal extension associated with extension of
11562-413: The old bucket line . This has improved the chances of finding gold. Smaller dredges with 50-to-100-millimetre (2 to 4 in) suction tubes are used to sample areas behind boulders and along potential pay streaks, until "colour" (gold) appears. Other larger scale dredging operations take place on exposed river gravel bars at seasonal low water. These operations typically use a land based excavator to feed
11685-696: The oldest being metasedimentary rocks from the Cambrian in the Mount Morrison region. These dark-colored hornfels , slates , marbles , and schists are found in the western foothills (notably around Coarsegold , west of the Tehachapi Pass ) and east of the Sierra Crest. The earliest granite of the Sierra started to form in the Triassic period. This granite is mostly found east of
11808-504: The oldest, largest, deepest, longest and richest gold mines in California". Between 1850 and its closure in 1956, the Empire Mine produced 5.8 million ounces (165 tons) of gold , extracted from 367 miles (591 km) of underground passages. In October 1850, George Roberts discovered gold in a quartz outcrop on Ophir Hill, but sold the claim in 1851 to Woodbury, Parks and Co. for $ 350 (or about $ 13,000 today, adjusted for inflation). The Woodbury Company consolidated several local claims into
11931-514: The picket line (the miners' lives depended on his engineering skills and they worked as a team). Bennett oversaw the closing of the Empire on May 28, 1957, when the last Cornish water pumps were shut and removed. In its final year of operation in 1956, the Empire Mine had reached an incline depth of 11,007 ft (3,355 m). In 1974 California State Parks purchased the Empire Mine surface property for $ 1.25 million ($ 7.72 million today), to create
12054-521: The plural ( Smokies , Rockies , Cascades , etc.), since Sierra is already pluralized in its native language, some locals who live in "the Sierra" are not hesitant to admonish those who refer to the area as "the Sierras". However, there are historical and literary references that use the plural, such as the 1871 collection of Joaquin Miller poems, Songs of the Sierras . Ansel Adams , in response to
12177-688: The possible respiratory problems that could be acquired, individuals may be exposed to hazardous chemicals used in gold extraction such as mercury and cyanide. These chemicals pose risks to gold miners, communities, and wildlife; resulting in further medical problems involving neurological disorders and waterborne diseases . Gold mining in some regions has been associated with conflicts over land rights, labour rights violations, and exploitation of vulnerable populations, including Indigenous peoples and artisanal miners. Mining activities can damage or destroy cultural heritage sites, artifacts, and sacred areas; further impacting cultural identities and heritages. In
12300-420: The range, produces a wind phenomenon known as the "Sierra Rotor". This is a horizontal rotation of the atmosphere just east of the crest of the Sierra, set in motion as an effect of strong westerly winds. Because of the large number of airplanes that have crashed in the Sierra Nevada, primarily due to the complex weather and atmospheric conditions such as downdrafts and microbursts caused by geography there,
12423-407: The recovery of gold from ore), can be highly toxic to people and wildlife even at relatively low concentrations. Illegal gold mining exacerbates the ecological vulnerability of the remaining forest ultimately leading to permanent forest loss. Gold mining clears native forests for mineral extraction, but also indirectly facilitates access to more land and further clearing. Rainforest recovery rates are
12546-559: The scars of hydraulic mining, since the resulting exposed earth and downstream gravel deposits do not support plant life. It is estimated that by 1855, at least 300,000 gold-seekers, merchants, and other immigrants had arrived in California from around the world. The huge numbers of newcomers brought by the Gold Rush drove Native Americans out of their traditional hunting, fishing and food-gathering areas. To protect their homes and livelihood, some Native Americans responded by attacking
12669-549: The sluice box. A rocker box uses less water than a sluice box and is well suited for areas where water is limited. A rocking motion provides the water movement needed for the gravity separation of gold in placer material. Rocker boxes gained popularity during the California Gold Rush in the 19th century and remain in use today. Although simple and inexpensive, it is not efficient as the previously discussed mining techniques . The dominant method for refining gold
12792-458: The southern Sierra was established to protect the endangered Sierra Nevada bighorn sheep . Starting in 1981, hikers were unable to enter the Area from May 15 through December 15, in order to protect the sheep. As of 2010, the restriction has been lifted and access to the Area is open for the whole year. The earliest rocks in the Sierra Nevada are metamorphic roof pendants of Paleozoic age,
12915-467: The surrounding rock or sediments. Unlike hard-rock mining, which involves excavating solid rock formations, water or dredging is used to extract the gold. Using a sluice box to extract gold from placer deposits has long been a very common practice in prospecting and small-scale mining. Sluices work on the principle that heavier particles will sink to the bottom of a stream, while those that are lighter will be carried downstream and expelled. A sluice box
13038-425: The survey. Men of the survey, including William H. Brewer , Charles F. Hoffmann and Clarence King , explored the backcountry of what would become Yosemite National Park in 1863. In 1864, they explored the area around Kings Canyon . In 1869, John Muir started his wanderings in the Sierra Nevada range, and in 1871, King was the first to climb Mount Langley , mistakenly believing he had summited Mount Whitney ,
13161-521: The suspension of operations below the 4,600-foot level by 1951. By the 1950s inflation costs for gold mining were leaving the operation unprofitable. In 1956 a crippling miners' strike over falling wages ended operations. Ellsworth Bennett, a 1910 graduate of the Mackay School of Mines in Reno was the last "Cap'n" (Superintendent) of the Empire, and the only person from management allowed across
13284-490: The term "Sierra Nevada" was a general identification of less familiar ranges toward the interior. In 1776, Pedro Font 's map applied the name to the range currently known as the Sierra Nevada. The literal translation is "snowy mountains", from sierra "a range of mountains", 1610s, from Spanish sierra "jagged mountain range", lit. "saw", from Latin serra "a saw"; and from fem. of Spanish nevado "snowy". While many mountain ranges are unanimously referred to in
13407-424: The water from an entire river into a sluice alongside the river, and then dig for gold in the newly exposed river bottom. By 1853, most of the easily accessible gold had been collected, and attention turned to extracting gold from more difficult locations. Hydraulic mining was used on ancient gold-bearing gravel beds on hillsides and bluffs in the gold fields. In hydraulic mining, a high-pressure hose directed
13530-529: The western half of the Sierra, while the later plutons formed in the eastern half of the Sierra. At this time, the Sierra Nevada formed the western ramp of a high plateau to the east, the Nevadaplano . During this period, rivers cut deep canyons into the range, generating topographic relief similar to the modern Sierra Nevada. This period of incision was halted approximately 30 million years ago by vast outpourings of pyroclastic flows from Nevada which filled
13653-509: The western side, and the Kawaiisu and Tübatulabal tribes in the southern Sierra. Today, some historic intertribal trade route trails over mountain passes are known artifact locations, such as Duck Pass with its obsidian arrowheads . The California and Sierra Native American tribes were predominantly peaceful, with occasional territorial disputes between the Paiute and Sierra Miwok tribes in
13776-511: The western slope up to the crest, since most of the precipitation has been wrung out at lower elevations. Most parts of the range east of the crest are in a rain shadow , and receive less than 25 inches of precipitation per year. While most summer days are dry, afternoon thunderstorms are common, particularly during the North American Monsoon in mid and late summer. Some of these summer thunderstorms drop over an inch of rain in
13899-538: The world's gold. Sometimes open-pit mining is used, such as at the Fort Knox Mine in central Alaska. Barrick Gold Corporation has one of the largest open-pit gold mines in North America located on its Goldstrike mine property in north eastern Nevada. Other gold mines use underground mining, where the ore is extracted through tunnels or shafts. South Africa has the world's deepest hard rock gold mine up to 3,900 metres (12,800 ft) underground. At such depths,
14022-720: The world, the Grasberg mine in Papua, Indonesia, is primarily a copper mine. Gold panning , or simply panning , is a form of placer mining and traditional mining that extracts gold from a placer deposit using a pan. The process is one of the simplest ways to extract gold, and is popular with geology enthusiasts especially because of its low cost and relative simplicity. The first recorded instances of placer mining are from ancient Rome , where gold and other precious metals were extracted from streams and mountainsides using sluices and panning ( ruina montium ). Placer mining
14145-663: Was China with 368.3 tonnes of gold mined in that year. The second-largest producer of gold was Russia where 331.1 tonnes was mined in the same year, followed by Australia with 327.8 tonnes. In 2023, the annual gold demand of 4,448 tonnes was 5% below that of 2022. The total gold demand in 2023 was the highest at 4,899 tonnes. Despite its decreasing content in ores, gold production is increasing. This increase can be achieved through ever larger-scale industrial installations as well as innovations, especially in hydrometallurgy . Hard rock mining extracts gold encased in rock, rather than fragments in loose sediment, and produces most of
14268-470: Was a major center for logging, with operations supplying lumber for the construction of mine structures, such as tunnels, shafts, and buildings, as well as fuel for the mines. Dan DeQuille observed in 1876, "the Comstock Lode may truthfully be said to be the tomb of the forests of the Sierra. Millions upon millions of feet of lumber are annually buried in the mines, nevermore to be resurrected.” In
14391-422: Was completed in 1923. Gold mining 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 volume of mining
14514-462: Was discovered in 1961. Official estimates indicate that total world gold production since the beginning of civilization has been around 6,352,216,000 troy ounces (197,576.0 t) and total gold production in Nevada is 1.1% of that, ranking Nevada as one of the Earth's primary gold-producing regions. World gold production was 3,612 tonnes in 2022. As of 2020 , the world's largest gold producer
14637-479: Was discovered, hundreds of miners would collaborate to put up a camp and stake their claims. Because the gold in the California gravel beds was so richly concentrated, the early forty-niners simply panned for gold in California's rivers and streams. However, panning cannot take place on a large scale, and miners and groups of miners graduated to more complex placer mining. Groups of prospectors would divert
14760-476: Was done by large corporations. However, the value of gold has led to millions of small, artisanal miners in many parts of the Global South . Like all mining, human rights and environmental issues are common in the gold mining industry, and can result in environmental conflict . In mines with less regulation, health and safety risks are much higher. The exact date that humans first began to mine gold
14883-440: Was first protected by the federal government in 1864. The Valley and Mariposa Grove were ceded to California in 1866 and turned into a state park. John Muir perceived overgrazing by sheep and logging of giant sequoia to be a problem in the Sierra. Muir successfully lobbied for the protection of the rest of Yosemite National Park: Congress created an Act to protect the park in 1890. The Valley and Mariposa Grove were added to
15006-626: Was mined extensively. The ancient Sumerians , around 2500 BCE, developed sophisticated techniques for extracting gold from alluvial deposits and underground mines. These techniques included the use of sluice boxes. Evidence suggests that Nubia had sporadic access to gold nuggets during the Neolithic and Prehistoric Period . Gold mining in Egypt involved both surface mining such as panning for gold in riverbeads and underground mining, where tunnels were dug to extract gold-bearing quartz veins. During
15129-531: Was the Cornish contribution of the Cornish engine , operated on steam, which emptied the depths of the mine of its constant water seepage at a rate of 18,000 US gal (68,000 L; 15,000 imp gal) per day. This enabled increased productivity and expansion underground. Starting in 1895, Lester Allan Pelton 's water wheel provided electric power for the mine and stamp mill . The Cornish provided
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