82-742: The Waitangiroto River is a river of the West Coast Region of New Zealand's South Island . It is approximately 15 km (9.3 mi) long, with its main source in the Waitangiroto swamp. It flows adjacent to the lower reaches of the Whataroa River and the Waitangitāhuna River . All three rivers enter the Tasman Sea northwest of the Okarito Lagoon . The first European exploration of
164-399: A fault . Water often lubricates faults, filling in fractures and jogs. About 10 kilometres (6.2 mi) below the surface, under very high temperatures and pressures, the water carries high concentrations of carbon dioxide, silica, and gold. During an earthquake, the fault jog suddenly opens wider. The water inside the void instantly vaporizes, flashing to steam and forcing silica, which forms
246-483: A dilute solution of gold(III) chloride or chlorauric acid . Unlike sulfur, phosphorus reacts directly with gold at elevated temperatures to produce gold phosphide (Au 2 P 3 ). Gold readily dissolves in mercury at room temperature to form an amalgam , and forms alloys with many other metals at higher temperatures. These alloys can be produced to modify the hardness and other metallurgical properties, to control melting point or to create exotic colors. Gold
328-572: A gold-from-seawater swindle in the United States in the 1890s, as did an English fraudster in the early 1900s. Fritz Haber did research on the extraction of gold from sea water in an effort to help pay Germany 's reparations following World War I . Based on the published values of 2 to 64 ppb of gold in seawater, a commercially successful extraction seemed possible. After analysis of 4,000 water samples yielding an average of 0.004 ppb, it became clear that extraction would not be possible, and he ended
410-830: A golden hue to metallic caesium . Common colored gold alloys include the distinctive eighteen-karat rose gold created by the addition of copper. Alloys containing palladium or nickel are also important in commercial jewelry as these produce white gold alloys. Fourteen-karat gold-copper alloy is nearly identical in color to certain bronze alloys, and both may be used to produce police and other badges . Fourteen- and eighteen-karat gold alloys with silver alone appear greenish-yellow and are referred to as green gold . Blue gold can be made by alloying with iron , and purple gold can be made by alloying with aluminium . Less commonly, addition of manganese , indium , and other elements can produce more unusual colors of gold for various applications. Colloidal gold , used by electron-microscopists,
492-552: A large alluvial deposit. The mines at Roşia Montană in Transylvania were also very large, and until very recently, still mined by opencast methods. They also exploited smaller deposits in Britain , such as placer and hard-rock deposits at Dolaucothi . The various methods they used are well described by Pliny the Elder in his encyclopedia Naturalis Historia written towards the end of
574-462: A novel type of metal-halide perovskite material consisting of Au and Au cations in its crystal structure has been found. It has been shown to be unexpectedly stable at normal conditions. Gold pentafluoride , along with its derivative anion, AuF − 6 , and its difluorine complex , gold heptafluoride , is the sole example of gold(V), the highest verified oxidation state. Some gold compounds exhibit aurophilic bonding , which describes
656-401: A sheet of 1 square metre (11 sq ft), and an avoirdupois ounce into 28 square metres (300 sq ft). Gold leaf can be beaten thin enough to become semi-transparent. The transmitted light appears greenish-blue because gold strongly reflects yellow and red. Such semi-transparent sheets also strongly reflect infrared light, making them useful as infrared (radiant heat) shields in
738-517: A solution of Au(OH) 3 in concentrated H 2 SO 4 produces red crystals of gold(II) sulfate , Au 2 (SO 4 ) 2 . Originally thought to be a mixed-valence compound, it has been shown to contain Au 4+ 2 cations, analogous to the better-known mercury(I) ion, Hg 2+ 2 . A gold(II) complex, the tetraxenonogold(II) cation, which contains xenon as a ligand, occurs in [AuXe 4 ](Sb 2 F 11 ) 2 . In September 2023,
820-470: Is Au with a half-life of 2.27 days. Gold's least stable isomer is Au with a half-life of only 7 ns. Au has three decay paths: β decay, isomeric transition , and alpha decay. No other isomer or isotope of gold has three decay paths. The possible production of gold from a more common element, such as lead , has long been a subject of human inquiry, and the ancient and medieval discipline of alchemy often focused on it; however,
902-696: Is Au , which decays by proton emission with a half-life of 30 μs. Most of gold's radioisotopes with atomic masses below 197 decay by some combination of proton emission , α decay , and β decay . The exceptions are Au , which decays by electron capture, and Au , which decays most often by electron capture (93%) with a minor β decay path (7%). All of gold's radioisotopes with atomic masses above 197 decay by β decay. At least 32 nuclear isomers have also been characterized, ranging in atomic mass from 170 to 200. Within that range, only Au , Au , Au , Au , and Au do not have isomers. Gold's most stable isomer
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#1733085282112984-648: Is also known, an example of a mixed-valence complex . Gold does not react with oxygen at any temperature and, up to 100 °C, is resistant to attack from ozone: Au + O 2 ⟶ ( no reaction ) {\displaystyle {\ce {Au + O2 ->}}({\text{no reaction}})} Au + O 3 → t < 100 ∘ C ( no reaction ) {\displaystyle {\ce {Au{}+O3->[{} \atop {t<100^{\circ }{\text{C}}}]}}({\text{no reaction}})} Some free halogens react to form
1066-520: Is also used in infrared shielding, the production of colored glass , gold leafing , and tooth restoration . Certain gold salts are still used as anti-inflammatory agents in medicine. Gold is the most malleable of all metals. It can be drawn into a wire of single-atom width, and then stretched considerably before it breaks. Such nanowires distort via the formation, reorientation, and migration of dislocations and crystal twins without noticeable hardening. A single gram of gold can be beaten into
1148-427: Is always richer at the exposed surface of gold-bearing veins, owing to the oxidation of accompanying minerals followed by weathering; and by washing of the dust into streams and rivers, where it collects and can be welded by water action to form nuggets. Gold sometimes occurs combined with tellurium as the minerals calaverite , krennerite , nagyagite , petzite and sylvanite (see telluride minerals ), and as
1230-559: Is at Shantytown . Other towns and settlements include: The West Coast region is governed by the West Coast Regional Council. Currently, it is chaired by Peter Haddock. The subnational gross domestic product (GDP) of the West Coast was estimated at NZ$ 2,373 million in the year to March 2022, 0.7% of New Zealand's national GDP. The regional GDP per capita was estimated at $ 72,127 in the same period. The region had one of
1312-513: Is attributed to wind-blown dust or rivers. At 10 parts per quadrillion, the Earth's oceans would hold 15,000 tonnes of gold. These figures are three orders of magnitude less than reported in the literature prior to 1988, indicating contamination problems with the earlier data. A number of people have claimed to be able to economically recover gold from sea water , but they were either mistaken or acted in an intentional deception. Prescott Jernegan ran
1394-464: Is found in ores in rock formed from the Precambrian time onward. It most often occurs as a native metal , typically in a metal solid solution with silver (i.e. as a gold/silver alloy ). Such alloys usually have a silver content of 8–10%. Electrum is elemental gold with more than 20% silver, and is commonly known as white gold . Electrum's color runs from golden-silvery to silvery, dependent upon
1476-874: Is in Greymouth. The region has been included in the "Top 10 Coastal Drives of the World" by Lonely Planet . The region has the only New Zealand nesting place of the kōtuku (white heron) , at the Waitangiroto Nature Reserve , visited by tours from the small farming township of Whataroa . This rare bird appears on the $ 2 coin. Over 80% of West Coast land is administered by the Department of Conservation, much of this being in National Parks. These include from north to south, parts of Kahurangi NP, Paparoa NP, parts of Arthurs Pass NP, Westland NP, parts of Aspiring NP plus
1558-465: Is most often called the oldest since this treasure is the largest and most diverse. Gold artifacts probably made their first appearance in Ancient Egypt at the very beginning of the pre-dynastic period, at the end of the fifth millennium BC and the start of the fourth, and smelting was developed during the course of the 4th millennium; gold artifacts appear in the archeology of Lower Mesopotamia during
1640-528: Is now questioned. The gold-bearing Witwatersrand rocks were laid down between 700 and 950 million years before the Vredefort impact. These gold-bearing rocks had furthermore been covered by a thick layer of Ventersdorp lavas and the Transvaal Supergroup of rocks before the meteor struck, and thus the gold did not actually arrive in the asteroid/meteorite. What the Vredefort impact achieved, however,
1722-427: Is red if the particles are small; larger particles of colloidal gold are blue. Gold has only one stable isotope , Au , which is also its only naturally occurring isotope, so gold is both a mononuclidic and monoisotopic element . Thirty-six radioisotopes have been synthesized, ranging in atomic mass from 169 to 205. The most stable of these is Au with a half-life of 186.1 days. The least stable
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#17330852821121804-553: Is resistant to most acids, though it does dissolve in aqua regia (a mixture of nitric acid and hydrochloric acid ), forming a soluble tetrachloroaurate anion . Gold is insoluble in nitric acid alone, which dissolves silver and base metals , a property long used to refine gold and confirm the presence of gold in metallic substances, giving rise to the term ' acid test '. Gold dissolves in alkaline solutions of cyanide , which are used in mining and electroplating . Gold also dissolves in mercury , forming amalgam alloys, and as
1886-484: Is similarly unaffected by most bases. It does not react with aqueous , solid , or molten sodium or potassium hydroxide . It does however, react with sodium or potassium cyanide under alkaline conditions when oxygen is present to form soluble complexes. Common oxidation states of gold include +1 (gold(I) or aurous compounds) and +3 (gold(III) or auric compounds). Gold ions in solution are readily reduced and precipitated as metal by adding any other metal as
1968-538: Is the least populous of New Zealand's sixteen regions. The West Coast is also the most sparsely populated region, with just 1.50 people per square kilometre (3.88 per square mile). West Coast Region had a population of 33,390 in the 2023 New Zealand census , an increase of 1,815 people (5.7%) since the 2018 census , and an increase of 1,242 people (3.9%) since the 2013 census . There were 17,031 males, 16,245 females and 117 people of other genders in 14,793 dwellings. 2.7% of people identified as LGBTIQ+ . The median age
2050-546: Is the only region of New Zealand where coal mining is still widely practiced. The name Westland is used by some New Zealanders to refer to the whole of the West Coast, including Grey District , Buller District and Fiordland , and can also refer to the short-lived Westland Province of 1873–76. Fiordland is on the west coast, but is in the Southland Region rather than the West Coast Region. Inhabitants of
2132-585: Is the soluble form of gold encountered in mining. The binary gold halides , such as AuCl , form zigzag polymeric chains, again featuring linear coordination at Au. Most drugs based on gold are Au(I) derivatives. Au(III) (referred to as auric) is a common oxidation state, and is illustrated by gold(III) chloride , Au 2 Cl 6 . The gold atom centers in Au(III) complexes, like other d compounds, are typically square planar , with chemical bonds that have both covalent and ionic character. Gold(I,III) chloride
2214-634: Is thought to have been delivered to Earth by asteroid impacts during the Late Heavy Bombardment , about 4 billion years ago. Gold which is reachable by humans has, in one case, been associated with a particular asteroid impact. The asteroid that formed Vredefort impact structure 2.020 billion years ago is often credited with seeding the Witwatersrand basin in South Africa with the richest gold deposits on earth. However, this scenario
2296-505: Is thought to have been produced in supernova nucleosynthesis , and from the collision of neutron stars , and to have been present in the dust from which the Solar System formed. Traditionally, gold in the universe is thought to have formed by the r-process (rapid neutron capture) in supernova nucleosynthesis , but more recently it has been suggested that gold and other elements heavier than iron may also be produced in quantity by
2378-416: Is unaffected by most acids. It does not react with hydrofluoric , hydrochloric , hydrobromic , hydriodic , sulfuric , or nitric acid . It does react with selenic acid , and is dissolved by aqua regia , a 1:3 mixture of nitric acid and hydrochloric acid . Nitric acid oxidizes the metal to +3 ions, but only in minute amounts, typically undetectable in the pure acid because of the chemical equilibrium of
2460-729: The Canterbury Plains and in the Firth of Thames , they have been almost completely destroyed for settlement and agriculture. Scenic areas include the Haast Pass , Fox and Franz Josef Glaciers , Hokitika Gorge , Lake Brunner , the Pancake Rocks at Punakaiki , the Oparara Arches and the Heaphy Track . The region has very high rainfall due to the prevailing northwesterly wind pattern and
2542-645: The Chu (state) circulated the Ying Yuan , one kind of square gold coin. In Roman metallurgy , new methods for extracting gold on a large scale were developed by introducing hydraulic mining methods, especially in Hispania from 25 BC onwards and in Dacia from 106 AD onwards. One of their largest mines was at Las Medulas in León , where seven long aqueducts enabled them to sluice most of
Waitangiroto River - Misplaced Pages Continue
2624-583: The Old Testament , starting with Genesis 2:11 (at Havilah ), the story of the golden calf , and many parts of the temple including the Menorah and the golden altar. In the New Testament , it is included with the gifts of the magi in the first chapters of Matthew. The Book of Revelation 21:21 describes the city of New Jerusalem as having streets "made of pure gold, clear as crystal". Exploitation of gold in
2706-581: The Taniwha ') is a region of New Zealand on the west coast of the South Island . It is administered by the West Coast Regional Council , and is known co-officially as Te Tai Poutini . It comprises the territorial authorities of Buller District , Grey District and Westland District . The principal towns are Westport , Greymouth and Hokitika . The region, one of the more remote areas of
2788-641: The Varna Necropolis near Lake Varna and the Black Sea coast, thought to be the earliest "well-dated" finding of gold artifacts in history. Several prehistoric Bulgarian finds are considered no less old – the golden treasures of Hotnitsa, Durankulak , artifacts from the Kurgan settlement of Yunatsite near Pazardzhik , the golden treasure Sakar, as well as beads and gold jewelry found in the Kurgan settlement of Provadia – Solnitsata ("salt pit"). However, Varna gold
2870-478: The Westland Province , until the abolition of the provincial system in 1876. The West Coast gold rush between 1864 and 1867 created numerous gold rush towns such as Ōkārito, which at one time was the largest town on the West Coast but quickly almost vanished as miners moved on. After that time, the population dwindled, but the main towns that still exist had become established. Following greenstone and gold,
2952-611: The noble metals . It is one of the least reactive chemical elements, being the second-lowest in the reactivity series . It is solid under standard conditions . Gold often occurs in free elemental ( native state ), as nuggets or grains, in rocks , veins , and alluvial deposits . It occurs in a solid solution series with the native element silver (as in electrum ), naturally alloyed with other metals like copper and palladium , and mineral inclusions such as within pyrite . Less commonly, it occurs in minerals as gold compounds, often with tellurium ( gold tellurides ). Gold
3034-470: The reducing agent . The added metal is oxidized and dissolves, allowing the gold to be displaced from solution and be recovered as a solid precipitate. Less common oxidation states of gold include −1, +2, and +5. The −1 oxidation state occurs in aurides, compounds containing the Au anion . Caesium auride (CsAu), for example, crystallizes in the caesium chloride motif; rubidium, potassium, and tetramethylammonium aurides are also known. Gold has
3116-399: The 2019–2020 season, there were 150,000 milking cows on the West Coast, 3.0% of the country's total herd. The cows produced 50,700 tonnes of milk solids, worth $ 365 million at the national average farmgate price ($ 7.20 per kg). Other industries are the manufacturing and sales of greenstone jewellery, sphagnum moss gathering and stone-collection for garden landscaping. Monteith's brewery
3198-623: The South Westland World Heritage Area. Each of these parks have flora and fauna common to all areas, as well as species, like kiwi, particular to those areas. Four roads run into the West Coast Region. The main road running the length of the region is State Highway 6 . It connects to the Tasman District in the north through the Buller Gorge , and to Otago in the south via Haast Pass . Two roads connect to Canterbury to
3280-623: The Taramakau River in 1864 by two Māori, Ihaia Tainui and Haimona Taukau. By the end of the year there were an estimated 1800 prospectors, many of them around the Hokitika area, which in 1866 was briefly the most populous settlement in New Zealand. The region was divided between Nelson Province and Canterbury Province from 1853: in 1873 the Canterbury portion of the region formed its own province,
3362-423: The Waitangiroto was on 30 December 1865, when surveyor Gerhard Mueller took a waka and paddled up what he called the "Waitangi-Roto", in search of a lake he had been told by local Māori was fifteen or twenty miles inland. He described the river as "quietly running, but very deep" in comparison to the nearby Waitangitoana. Mueller navigated six miles up the river before it branched into many small arms and his route
Waitangiroto River - Misplaced Pages Continue
3444-536: The West Coast are colloquially known as "Coasters". The region reaches from Kahurangi Point in the north to Awarua Point in the south, a distance of 600 km. It has an area of 23,246 km . To the west is the Tasman Sea (which like the Southern Ocean can be very rough, with four-metre swells common), and to the east are the Southern Alps . Much of the land is rugged, with a coastal plain where much of
3526-415: The area was famous across New Zealand for its richness in pounamu greenstone. Kāi Tahu traded millions of modern New Zealand dollars ' worth of the stone across New Zealand , making Te Tai Poutini one of the wealthiest regions in the country. After the arrival of Europeans, the region became famed for its vast and mostly untapped gold reserves, which historically had not been highly valued. The region
3608-420: The census question. Of those at least 15 years old, 2,658 (9.5%) people had a bachelor's or higher degree, 15,825 (56.6%) had a post-high school certificate or diploma, and 8,490 (30.4%) people exclusively held high school qualifications. The median income was $ 32,700, compared with $ 41,500 nationally. 1,956 people (7.0%) earned over $ 100,000 compared to 12.1% nationally. The employment status of those at least 15
3690-1409: The corresponding gold halides. Gold is strongly attacked by fluorine at dull-red heat to form gold(III) fluoride AuF 3 . Powdered gold reacts with chlorine at 180 °C to form gold(III) chloride AuCl 3 . Gold reacts with bromine at 140 °C to form a combination of gold(III) bromide AuBr 3 and gold(I) bromide AuBr, but reacts very slowly with iodine to form gold(I) iodide AuI: 2 Au + 3 F 2 → Δ 2 AuF 3 {\displaystyle {\ce {2Au{}+3F2->[{} \atop \Delta ]2AuF3}}} 2 Au + 3 Cl 2 → Δ 2 AuCl 3 {\displaystyle {\ce {2Au{}+3Cl2->[{} \atop \Delta ]2AuCl3}}} 2 Au + 2 Br 2 → Δ AuBr 3 + AuBr {\displaystyle {\ce {2Au{}+2Br2->[{} \atop \Delta ]AuBr3{}+AuBr}}} 2 Au + I 2 → Δ 2 AuI {\displaystyle {\ce {2Au{}+I2->[{} \atop \Delta ]2AuI}}} Gold does not react with sulfur directly, but gold(III) sulfide can be made by passing hydrogen sulfide through
3772-551: The country, is also the most sparsely populated. With a population of just 32,900 people, the West Coast is the least populous region in New Zealand. The population in the region grew by 0.4% over the year to July 2023. The region has a rich and important history. The land itself is ancient, stretching back to the Carboniferous period ; this is evident by the amount of carboniferous materials naturally found there, especially coal . First settled by Kāi Tahu in approximately 1200 AD,
3854-424: The densest element, osmium , is 22.588 ± 0.015 g/cm . Whereas most metals are gray or silvery white, gold is slightly reddish-yellow. This color is determined by the frequency of plasma oscillations among the metal's valence electrons, in the ultraviolet range for most metals but in the visible range for gold due to relativistic effects affecting the orbitals around gold atoms. Similar effects impart
3936-664: The early 4th millennium. As of 1990, gold artifacts found at the Wadi Qana cave cemetery of the 4th millennium BC in West Bank were the earliest from the Levant. Gold artifacts such as the golden hats and the Nebra disk appeared in Central Europe from the 2nd millennium BC Bronze Age . The oldest known map of a gold mine was drawn in the 19th Dynasty of Ancient Egypt (1320–1200 BC), whereas
4018-424: The east, State Highway 7 through Lewis Pass to North Canterbury and State Highway 73 via Arthur's Pass to Christchurch . The Midland railway line is the only railway line into the region. It links to Christchurch via Arthur's Pass. The TranzAlpine train service runs return between Christchurch and Greymouth daily and freight lines extend to Ngākawau and Hokitika . Daily passenger flights operate into
4100-574: The first written reference to gold was recorded in the 12th Dynasty around 1900 BC. Egyptian hieroglyphs from as early as 2600 BC describe gold, which King Tushratta of the Mitanni claimed was "more plentiful than dirt" in Egypt. Egypt and especially Nubia had the resources to make them major gold-producing areas for much of history. One of the earliest known maps, known as the Turin Papyrus Map , shows
4182-403: The gold acts simply as a solute, this is not a chemical reaction . A relatively rare element, gold is a precious metal that has been used for coinage , jewelry , and other works of art throughout recorded history . In the past, a gold standard was often implemented as a monetary policy . Gold coins ceased to be minted as a circulating currency in the 1930s, and the world gold standard
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#17330852821124264-563: The highest electron affinity of any metal, at 222.8 kJ/mol, making Au a stable species, analogous to the halides . Gold also has a –1 oxidation state in covalent complexes with the group 4 transition metals, such as in titanium tetraauride and the analogous zirconium and hafnium compounds. These chemicals are expected to form gold-bridged dimers in a manner similar to titanium(IV) hydride . Gold(II) compounds are usually diamagnetic with Au–Au bonds such as [ Au(CH 2 ) 2 P(C 6 H 5 ) 2 ] 2 Cl 2 . The evaporation of
4346-540: The location of the Southern Alps, which give rise to heavy orographic precipitation . The rain shadow effect is responsible for the relatively arid climate of the Canterbury Plains on the other side of the Southern Alps. The region is home to Ngāi Tahu , who value it for the greenstone (pounamu) found there in abundance. The region was only occasionally visited by Europeans until the discovery of gold near
4428-542: The mineral quartz, and gold out of the fluids and onto nearby surfaces. The world's oceans contain gold. Measured concentrations of gold in the Atlantic and Northeast Pacific are 50–150 femtomol /L or 10–30 parts per quadrillion (about 10–30 g/km ). In general, gold concentrations for south Atlantic and central Pacific samples are the same (~50 femtomol/L) but less certain. Mediterranean deep waters contain slightly higher concentrations of gold (100–150 femtomol/L), which
4510-581: The next valuable mineral was coal. Discovered near the Buller River in the mid-1840s, mining began in earnest during the 1860s. By the 1880s coal had become the region's main industry, with mines throughout the northern half of the region, especially around Westport . Many of these continued in operation until the mid-20th century, and several survive. Timber has also long been a major industry, although in recent years there has been an uneasy balance between forestry for wood and forestry for conservation. Much of
4592-411: The noble metals, it still forms many diverse compounds. The oxidation state of gold in its compounds ranges from −1 to +5, but Au(I) and Au(III) dominate its chemistry. Au(I), referred to as the aurous ion, is the most common oxidation state with soft ligands such as thioethers , thiolates , and organophosphines . Au(I) compounds are typically linear. A good example is Au(CN) − 2 , which
4674-563: The plan of a gold mine in Nubia together with indications of the local geology . The primitive working methods are described by both Strabo and Diodorus Siculus , and included fire-setting . Large mines were also present across the Red Sea in what is now Saudi Arabia . Gold is mentioned in the Amarna letters numbered 19 and 26 from around the 14th century BC. Gold is mentioned frequently in
4756-399: The population resides. It is divided into the three local government districts of (from north to south) Buller , Grey and Westland . The land is very scenic, with wild coastlines, mountains and a very high proportion of native bush , much of it native temperate rain forest . It is the only part of New Zealand where significant tracts of lowland forest remain: elsewhere, for instance on
4838-459: The project. The earliest recorded metal employed by humans appears to be gold, which can be found free or " native ". Small amounts of natural gold have been found in Spanish caves used during the late Paleolithic period, c. 40,000 BC . The oldest gold artifacts in the world are from Bulgaria and are dating back to the 5th millennium BC (4,600 BC to 4,200 BC), such as those found in
4920-681: The r-process in the collision of neutron stars . In both cases, satellite spectrometers at first only indirectly detected the resulting gold. However, in August 2017, the spectroscopic signatures of heavy elements, including gold, were observed by electromagnetic observatories in the GW170817 neutron star merger event, after gravitational wave detectors confirmed the event as a neutron star merger. Current astrophysical models suggest that this single neutron star merger event generated between 3 and 13 Earth masses of gold. This amount, along with estimations of
5002-620: The rare bismuthide maldonite ( Au 2 Bi ) and antimonide aurostibite ( AuSb 2 ). Gold also occurs in rare alloys with copper , lead , and mercury : the minerals auricupride ( Cu 3 Au ), novodneprite ( AuPb 3 ) and weishanite ( (Au,Ag) 3 Hg 2 ). A 2004 research paper suggests that microbes can sometimes play an important role in forming gold deposits, transporting and precipitating gold to form grains and nuggets that collect in alluvial deposits. A 2013 study has claimed water in faults vaporizes during an earthquake, depositing gold. When an earthquake strikes, it moves along
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#17330852821125084-420: The rate of occurrence of these neutron star merger events, suggests that such mergers may produce enough gold to account for most of the abundance of this element in the universe. Because the Earth was molten when it was formed , almost all of the gold present in the early Earth probably sank into the planetary core . Therefore, as hypothesized in one model, most of the gold in the Earth's crust and mantle
5166-935: The reaction. However, the ions are removed from the equilibrium by hydrochloric acid, forming AuCl − 4 ions, or chloroauric acid , thereby enabling further oxidation: 2 Au + 6 H 2 SeO 4 → 200 ∘ C Au 2 ( SeO 4 ) 3 + 3 H 2 SeO 3 + 3 H 2 O {\displaystyle {\ce {2Au{}+6H2SeO4->[{} \atop {200^{\circ }{\text{C}}}]Au2(SeO4)3{}+3H2SeO3{}+3H2O}}} Au + 4 HCl + HNO 3 ⟶ HAuCl 4 + NO ↑ + 2 H 2 O {\displaystyle {\ce {Au{}+4HCl{}+HNO3->HAuCl4{}+NO\uparrow +2H2O}}} Gold
5248-510: The region is public land administered by the Department of Conservation and the region has some of the best remaining stands of native forest, along with a wealth of rare wildlife. Ecotourism is now an important industry, and this goes hand in hand with the conservation efforts. The West Coast region covers 23,245.52 km (8,975.15 sq mi) and has an estimated population of 34,800 as of June 2024, 0.7% of New Zealand's population. It
5330-430: The region. Air New Zealand flies between Christchurch and Hokitika and Sounds Air between Wellington and Westport. Gold Gold is a chemical element with the chemical symbol Au (from Latin aurum ) and atomic number 79. In its pure form, it is a bright , slightly orange-yellow, dense, soft, malleable , and ductile metal . Chemically, gold is a transition metal , a group 11 element , and one of
5412-464: The rest of the gold on Earth is thought to have been incorporated into the planet since its very beginning, as planetesimals formed the mantle . In 2017, an international group of scientists established that gold "came to the Earth's surface from the deepest regions of our planet", the mantle, as evidenced by their findings at Deseado Massif in the Argentinian Patagonia . On Earth, gold
5494-474: The same result and showing that the isotopes of gold produced by it were all radioactive . In 1980, Glenn Seaborg transmuted several thousand atoms of bismuth into gold at the Lawrence Berkeley Laboratory. Gold can be manufactured in a nuclear reactor, but doing so is highly impractical and would cost far more than the value of the gold that is produced. Although gold is the most noble of
5576-484: The silver content. The more silver, the lower the specific gravity . Native gold occurs as very small to microscopic particles embedded in rock, often together with quartz or sulfide minerals such as " fool's gold ", which is a pyrite . These are called lode deposits. The metal in a native state is also found in the form of free flakes, grains or larger nuggets that have been eroded from rocks and end up in alluvial deposits called placer deposits . Such free gold
5658-627: The site. In 1967, a major flood caused the Waitangitāhuna River to breach its banks and establish a branch with a new course to Lake Wahapo . The Waitangiroto River changed course away from the lagoon at its mouth and formed a new route to the sea. Both of these changes were seen as significant risk to the white heron breeding colony. 43°08′S 170°14′E / 43.133°S 170.233°E / -43.133; 170.233 West Coast Region The West Coast ( Māori : Te Tai Poutini , lit. 'The Coast of Poutini,
5740-446: The south-east corner of the Black Sea is said to date from the time of Midas , and this gold was important in the establishment of what is probably the world's earliest coinage in Lydia around 610 BC. The legend of the golden fleece dating from eighth century BCE may refer to the use of fleeces to trap gold dust from placer deposits in the ancient world. From the 6th or 5th century BC,
5822-422: The strongest growing regional economies of New Zealand in 2022, though from a rather small base. Industries include mining for coal and alluvial gold , forestry and wood processing, fishing (including whitebaiting ), tourism and farming. Dairy farming has grown strongly – the local dairy co-operative Westland Milk Products remained independent when most others merged to form Fonterra in 2001. In
5904-481: The sun. It was a glorious sight—I gave up pulling, and watched the tribe for a long time. They were not at all shy—kept up a continual 'plappering' amongst themselves, and seemed to be astonished at me more than afraid.…I am glad now I had no gun with me—it would have been a pity to disturb this peaceful community." The Waitangiroto Nature Reserve , located on the river, is the only nesting area for kōtuku in New Zealand. Royal spoonbills and little shag also breed at
5986-436: The tendency of gold ions to interact at distances that are too long to be a conventional Au–Au bond but shorter than van der Waals bonding . The interaction is estimated to be comparable in strength to that of a hydrogen bond . Well-defined cluster compounds are numerous. In some cases, gold has a fractional oxidation state. A representative example is the octahedral species {Au( P(C 6 H 5 ) 3 )} 2+ 6 . Gold
6068-403: The transmutation of the chemical elements did not become possible until the understanding of nuclear physics in the 20th century. The first synthesis of gold was conducted by Japanese physicist Hantaro Nagaoka , who synthesized gold from mercury in 1924 by neutron bombardment. An American team, working without knowledge of Nagaoka's prior study, conducted the same experiment in 1941, achieving
6150-417: The visors of heat-resistant suits and in sun visors for spacesuits . Gold is a good conductor of heat and electricity . Gold has a density of 19.3 g/cm , almost identical to that of tungsten at 19.25 g/cm ; as such, tungsten has been used in the counterfeiting of gold bars , such as by plating a tungsten bar with gold. By comparison, the density of lead is 11.34 g/cm , and that of
6232-558: Was 48.1 years (compared with 38.1 years nationally). There were 5,448 people (16.3%) aged under 15 years, 4,518 (13.5%) aged 15 to 29, 15,861 (47.5%) aged 30 to 64, and 7,563 (22.7%) aged 65 or older. People could identify as more than one ethnicity. The results were 89.7% European ( Pākehā ); 13.5% Māori ; 1.6% Pasifika ; 4.0% Asian ; 0.5% Middle Eastern, Latin American and African New Zealanders (MELAA); and 4.3% other, which includes people giving their ethnicity as "New Zealander". English
6314-783: Was abandoned for a fiat currency system after the Nixon shock measures of 1971. In 2020, the world's largest gold producer was China, followed by Russia and Australia. As of 2020 , a total of around 201,296 tonnes of gold exist above ground. This is equal to a cube, with each side measuring roughly 21.7 meters (71 ft). The world's consumption of new gold produced is about 50% in jewelry, 40% in investments , and 10% in industry . Gold's high malleability, ductility, resistance to corrosion and most other chemical reactions, as well as conductivity of electricity have led to its continued use in corrosion-resistant electrical connectors in all types of computerized devices (its chief industrial use). Gold
6396-417: Was blocked by fallen trees. He noted there was dense bush on both sides, "beautiful Kowhai trees abounding and almost all shrubs in flower…" He also came across a "cranery": a nesting colony of the kōtuku ( Ardea alba modesta ): "Of these birds (near 4 ft. high) imagine seeing around you from 50 to 60, sitting on high pines and lower trees, in a circle of about 150 yards, their pure white feathers shining in
6478-556: Was spoken by 98.0%, Māori language by 2.3%, Samoan by 0.2% and other languages by 5.6%. No language could be spoken by 1.5% (e.g. too young to talk). New Zealand Sign Language was known by 0.5%. The percentage of people born overseas was 13.2, compared with 28.8% nationally. Religious affiliations were 29.8% Christian , 0.6% Hindu , 0.2% Islam , 0.3% Māori religious beliefs , 0.4% Buddhist , 0.7% New Age , 0.1% Jewish , and 1.2% other religions. People who answered that they had no religion were 57.8%, and 9.0% of people did not answer
6560-467: Was subsequently settled by thousands of Irish Catholics after the Irish Famine , who constitute the majority of the population, alongside the indigenous Kāi Tahu and those who come from admixing between the two populations. The region was also heavily sought after by nuclear weapons states in the 1950s for its abundant resources of uranium , which many West Coasters found objectionable. The West Coast
6642-487: Was that 12,819 (45.9%) people were employed full-time, 4,101 (14.7%) were part-time, and 687 (2.5%) were unemployed. There are only four towns with a population over 1,000: Greymouth , Westport , Hokitika and Runanga . These four towns, plus Reefton (population 980), are recognised as urban areas by Statistics New Zealand. During the gold rush days, Hokitika had a population of more than 25,000 with more than 100 pubs . A recreation of an early New Zealand settlement
6724-605: Was to distort the Witwatersrand basin in such a way that the gold-bearing rocks were brought to the present erosion surface in Johannesburg , on the Witwatersrand , just inside the rim of the original 300 km (190 mi) diameter crater caused by the meteor strike. The discovery of the deposit in 1886 launched the Witwatersrand Gold Rush . Some 22% of all the gold that is ascertained to exist today on Earth has been extracted from these Witwatersrand rocks. Much of
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