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111-615: In 2014, the hospital in Bertoua became known for its work serving the medical needs of refugees from the Central African Republic crossing into Cameroon at border towns such as Gbiti . 4°35′N 13°41′E  /  4.583°N 13.683°E  / 4.583; 13.683 This Cameroon location article is a stub . You can help Misplaced Pages by expanding it . Central African Republic The Central African Republic ( CAR ), formerly known as Ubangi-Shari ,

222-399: 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

333-422: A wet season that lasts from June to September in the northern regions of the country, and from May to October in the south. During the wet season, rainstorms are an almost daily occurrence, and early morning fog is commonplace. Maximum annual precipitation is approximately 1,800 millimetres (71 in) in the upper Ubangi region. The northern areas are hot and humid from February to May, but can be subject to

444-551: A 2018 Forest Landscape Integrity Index mean score of 9.28/10, ranking it seventh globally out of 172 countries. In 2008, Central African Republic was the world's least light pollution affected country. The Central African Republic is the focal point of the Bangui Magnetic Anomaly , one of the largest magnetic anomalies on Earth. The climate of the Central African Republic is generally tropical , with

555-730: A U.N. peacekeeping force (MINURCA) . Since 1997, the country has hosted almost a dozen peacekeeping interventions, earning it the title of "world champion of peacekeeping". In 1998, parliamentary elections resulted in Kolingba's RDC winning 20 out of 109 seats. The next year, however, in spite of widespread public anger in urban centers over his corrupt rule, Patassé won a second term in the presidential election. On 28 May 2001, rebels stormed strategic buildings in Bangui in an unsuccessful coup attempt . The army chief of staff, Abel Abrou, and General François N'Djadder Bedaya were killed, but Patassé regained

666-468: A company owned by one of his wives. The government violently suppressed the protests, killing 100 children and teenagers. Bokassa might have been personally involved in some of the killings. In September 1979, France overthrew Bokassa and restored Dacko to power (subsequently restoring the official name of the country and the original government to the Central African Republic). Dacko, in turn,

777-483: 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

888-572: 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

999-830: 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,

1110-431: A land area of about 620,000 square kilometres (240,000 sq mi). As of 2024, it has a population of 5,357,744, and is in the scene of a civil war , which has been ongoing since 2012. As a former French colony , French is the official language, with Sango, a Ngbandi based-creole language as the national and co- official language . The Central African Republic mainly consists of Sudano-Guinean savannas , but

1221-552: 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

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1332-592: A new constitution, and announced that he would step down and run for office once the new constitution was approved. In 2004, the Central African Republic Bush War began as forces opposed to Bozizé took up arms against his government. In May 2005, Bozizé won the presidential election, which excluded Patassé, and in 2006 fighting continued between the government and the rebels. In November 2006, Bozizé's government requested French military support to help them repel rebels who had taken control of towns in

1443-462: 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

1554-632: A plane crash on 29 March 1959, his cousin, David Dacko , took control of MESAN. Dacko became the country's first president when the Central African Republic formally received independence from France at midnight on 13 August 1960, a date celebrated by the country's Independence Day holiday. Dacko threw out his political rivals, including Abel Goumba , former Prime Minister and leader of Mouvement d'évolution démocratique de l'Afrique centrale (MEDAC), whom he forced into exile in France. With all opposition parties suppressed by November 1962, Dacko declared MESAN as

1665-510: A power-sharing government. The deal later broke down, and the rebels seized the capital in March 2013 and Bozizé fled the country. Michel Djotodia took over as president. Prime Minister Nicolas Tiangaye requested a UN peacekeeping force from the UN Security Council and on 31 May former President Bozizé was indicted for crimes against humanity and incitement to genocide. By the end of

1776-720: A second round of elections were finally held in 1993, again with the help of the international community coordinated by GIBAFOR, Ange-Félix Patassé won in the second round of voting with 53% of the vote while Goumba won 45.6%. Patassé's party, the Mouvement pour la Libération du Peuple Centrafricain (MLPC) or Movement for the Liberation of the Central African People, gained a plurality (relative majority) but not an absolute majority of seats in parliament, which meant Patassé's party required coalition partners. Patassé purged many of

1887-401: 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

1998-517: 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,

2109-444: A surprise attack against Patassé, who was out of the country. Libyan troops and some 1,000 soldiers of Bemba's Congolese rebel organization failed to stop the rebels and Bozizé's forces succeeded in overthrowing Patassé. François Bozizé suspended the constitution and named a new cabinet, which included most opposition parties. Abel Goumba was named vice-president. Bozizé established a broad-based National Transition Council to draft

2220-470: 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,

2331-696: 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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2442-417: 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 the noble metals . It is one of the least reactive chemical elements, being the second-lowest in the reactivity series . It

2553-690: Is a landlocked country in Central Africa . It is bordered by Chad to the north , Sudan to the northeast , South Sudan to the east , the Democratic Republic of the Congo to the south , the Republic of the Congo to the southwest , and Cameroon to the west . Bangui is the country's capital and largest city, bordering the Democratic Republic of the Congo. The Central African Republic covers

2664-693: Is a member of the United Nations , the African Union , the Economic Community of Central African States , the Organisation internationale de la Francophonie and the Non-Aligned Movement . The name of the Central African Republic is derived from the country's geographical location in the central region of Africa and its republican form of government. From 1976 to 1979, the country was known as

2775-648: 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

2886-520: 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

2997-427: 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

3108-472: Is argued that the focus of the initial disarmament efforts exclusively on the Seleka inadvertently handed the anti-Balaka the upper hand, leading to the forced displacement of Muslim civilians by anti-Balaka in Bangui and western Central African Republic. On 11 January 2014, Michael Djotodia and Nicolas Tiengaye resigned as part of a deal negotiated at a regional summit in neighboring Chad . Catherine Samba-Panza

3219-513: 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

3330-464: 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

3441-465: 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

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3552-528: 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,

3663-427: 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

3774-553: 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

3885-484: 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

3996-483: 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

4107-585: 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

4218-634: 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

4329-505: 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

4440-458: Is today the Central and East Central African Republic while some Bantu people migrated from the southwest of Cameroon . Bananas arrived in the region during the first millennium BCE and added an important source of carbohydrates to the diet; they were also used in the production of alcoholic beverages . Production of copper , salt , dried fish , and textiles dominated the economic trade in

4551-416: 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

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4662-589: The Central African Empire . During the colonial era, the country's name was Ubangi-Shari ( French : Oubangui-Chari ), a name derived from two major rivers and Central African waterways – Ubangi and Chari . Barthélemy Boganda , the country's first prime minister , favored the name "Central African Republic" over Ubangi-Shari, reportedly because he envisioned a larger union of countries in Central Africa . Approximately 10,000 years ago, desertification forced hunter-gatherer societies south into

4773-645: 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

4884-685: The Congo-Ocean Railway . Through the period of construction until 1934 there was a continual heavy cost in human lives, with total deaths among all workers along the railway estimated in excess of 17,000 of the construction workers, from a combination of both industrial accidents and diseases including malaria . In 1928, a major insurrection, the Kongo-Wara rebellion or 'war of the hoe handle', broke out in Western Ubangi-Shari and continued for several years. The extent of this insurrection, which

4995-648: The Free French Forces in Bangui . In 1946 Barthélemy Boganda was elected with 9,000 votes to the French National Assembly , becoming the first representative of the Central African Republic in the French government. Boganda maintained a political stance against racism and the colonial regime but gradually became disheartened with the French political system and returned to the Central African Republic to establish

5106-483: The Human Development Index (HDI), the country had the third-lowest level of human development, ranking 191 out of 193 countries. The country had the second lowest inequality-adjusted Human Development Index (IHDI), ranking 164th out of 165 countries. The Central African Republic is also estimated to be the unhealthiest country as well as the worst country in which to be young. The Central African Republic

5217-639: The Movement for the Social Evolution of Black Africa ( Mouvement pour l'évolution sociale de l'Afrique noire , MESAN) in 1950. In the Ubangi-Shari Territorial Assembly election in 1957, MESAN captured 347,000 out of the total 356,000 votes and won every legislative seat, which led to Boganda being elected president of the Grand Council of French Equatorial Africa and vice-president of

5328-583: 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

5439-573: The Peace Corps evacuated all its volunteers to neighboring Cameroon. To date, the Peace Corps has not returned to the Central African Republic. The Bangui Agreements , signed in January 1997, provided for the deployment of an inter-African military mission, to the Central African Republic and re-entry of ex-mutineers into the government on 7 April 1997. The inter-African military mission was later replaced by

5550-641: 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

5661-767: The fall of the Berlin Wall , a pro-democracy movement arose. Pressure from the United States, France, and from a group of locally represented countries and agencies called GIBAFOR (France, the US, Germany, Japan, the EU, the World Bank , and the United Nations ) finally led Kolingba to agree, in principle, to hold free elections in October 1992 with help from the UN Office of Electoral Affairs. After using

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5772-470: 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

5883-770: The 18th century Bandia-Nzakara Azande peoples established the Bangassou Kingdom along the Ubangi River . In the mid 19th century, the Bobangi people became major slave traders and sold their captives to the Americas using the Ubangi river to reach the coast. In 1875, the Sudanese sultan Rabih az-Zubayr governed Upper-Oubangui, which included present-day Central African Republic. The European invasion of Central African territory began in

5994-561: The Central African Republic is the world's 44th-largest country . Much of the southern border is formed by tributaries of the Congo River ; the Mbomou River in the east merges with the Uele River to form the Ubangi River , which also comprises portions of the southern border. The Sangha River flows through some of the western regions of the country, while the eastern border lies along

6105-668: The Central African Republic...a 'vassal state' of the Kremlin." The Central African Republic is a landlocked nation within the interior of the African continent. It is bordered by Cameroon, Chad, Sudan, South Sudan, the Democratic Republic of the Congo, and the Republic of the Congo. The country lies between latitudes 2° and 11°N , and longitudes 14° and 28°E . Much of the country consists of flat or rolling plateau savanna approximately 500 metres (1,640 ft) above sea level . In addition to

6216-725: The Central African region. In the 16th and 17th centuries, slave traders began to raid the region as part of the expansion of the Saharan and Nile River slave routes. Their captives were enslaved and shipped to the Mediterranean coast, Europe, Arabia, the Western Hemisphere, or to the slave ports and factories along the West and North Africa or South along the Ubangui and Congo rivers. During

6327-676: The Fertit Hills in the northeast of the Central African Republic, there are scattered hills in the southwest regions. In the northwest is the Yade Massif, a granite plateau with an altitude of 348 metres (1,143 ft). The Central African Republic contains six terrestrial ecoregions: Northeastern Congolian lowland forests , Northwestern Congolian lowland forests , Western Congolian swamp forests , East Sudanian savanna , Northern Congolian forest-savanna mosaic , and Sahelian Acacia savanna . At 622,984 square kilometres (240,535 sq mi),

6438-557: The Kolingba elements from the government and Kolingba supporters accused Patassé's government of conducting a " witch hunt " against the Yakoma. A new constitution was approved on 28 December 1994 but had little impact on the country's politics. In 1996–1997, reflecting steadily decreasing public confidence in the government's erratic behavior, three mutinies against Patassé's administration were accompanied by widespread destruction of property and heightened ethnic tension. During this time (1996),

6549-571: The Sahel regions of northern Central Africa, where some groups settled. Farming began as part of the Neolithic Revolution . Initial farming of white yam progressed into millet and sorghum , and before 3000   BCE the domestication of African oil palm improved the groups' nutrition and allowed for expansion of the local populations. This agricultural revolution, combined with a "Fish-stew Revolution", in which fishing began to take place and

6660-522: The U.S. ambassador to the United Nations, said 417 of the country's 436 mosques had been destroyed, and Muslim women were so scared of going out in public they were giving birth in their homes instead of going to the hospital. On 14 December 2015, Séléka rebel leaders declared an independent Republic of Logone . Presidential elections were held in December 2015. As no candidate received more than 50% of

6771-425: The Ubangi-Shari Government Council. Within a year, he declared the establishment of the Central African Republic and served as the country's first prime minister. MESAN continued to exist, but its role was limited. The Central African Republic was granted autonomy within the French Community on 1 December 1958, a status which meant it was still counted as part of the French Empire in Africa. After Boganda's death in

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6882-1409: 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

6993-446: The country also includes a Sahelo - Sudanian zone in the north and an equatorial forest zone in the south. Two-thirds of the country is within the Ubangi River basin (which flows into the Congo ), while the remaining third lies in the basin of the Chari , which flows into Lake Chad . What is today the Central African Republic has been inhabited since at least 8,000 BCE. The country's borders were established by France, which ruled

7104-408: The country as a colony starting in the late 19th century. After gaining independence from France in 1960, the Central African Republic was ruled by a series of autocratic leaders, including an abortive attempt at a monarchy under the regime of Jean-Bedel Bokassa . By the 1990s, calls for democracy led to the first multi-party democratic elections in 1993. Ange-Félix Patassé became president, but

7215-423: The country's northern regions. Though the initial public details of the agreement pertained to logistics and intelligence, by December the French assistance included airstrikes by Dassault Mirage 2000 fighters against rebel positions. The Syrte Agreement in February and the Birao Peace Agreement in April 2007 called for a cessation of hostilities, the billeting of FDPC fighters and their integration with FACA,

7326-426: The country. Some 800 of the country's polling stations, or 14% of the total, were closed due to violence. Three Burundian peacekeepers were killed and an additional two were wounded during the run-up to the election. President Faustin-Archange Touadéra was reelected in the first round of the election in December 2020. Russian mercenaries from the Wagner Group have supported President Faustin-Archange Touadéra in

7437-538: The country. On 18 February 2014, United Nations Secretary-General Ban Ki-moon called on the UN Security Council to immediately deploy 3,000 troops to the country, bolstering the 6,000 African Union soldiers and 2,000 French troops already in the country, to combat civilians being murdered in large numbers. The Séléka government was said to be divided, and in September 2013, Djotodia officially disbanded Seleka, but many rebels refused to disarm, becoming known as ex-Seleka, and veered further out of government control. It

7548-424: 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

7659-409: 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

7770-413: The edge of the Nile River watershed . It has been estimated that up to 8% of the country is covered by forest, with the densest parts generally located in the southern regions. The forests are highly diverse and include commercially important species of Ayous , Sapelli , and Sipo . The deforestation rate is about 0.4% per annum, and lumber poaching is commonplace. The Central African Republic had

7881-407: The excuse of alleged irregularities to suspend the results of the elections as a pretext for holding on to power, President Kolingba came under intense pressure from GIBAFOR to establish a "Conseil National Politique Provisoire de la République" (Provisional National Political Council, CNPPR) and to set up a "Mixed Electoral Commission", which included representatives from all political parties. When

7992-529: The fears of widespread violence were ultimately unfounded, and the African Union regarded the elections as successful. Touadéra was sworn in on 30 March 2016. No representatives of the Seleka rebel group or the "anti-balaka" militias were included in the subsequently formed government. After the end of Touadéra's first term, presidential elections were held on 27 December 2020 with a possible second round planned for 14 February 2021. Former president François Bozizé announced his candidacy on 25 July 2020 but

8103-469: The fight against rebels. Russia's Wagner group has been accused of harassing and intimidating civilians. In December 2022, Roger Cohen wrote in The New York Times , " Wagner shock troops form a Praetorian Guard for Mr. Touadéra, who is also protected by Rwandan forces, in return for an untaxed license to exploit and export the Central African Republic's resources" and "one Western ambassador called

8214-574: 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

8325-403: 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

8436-563: 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

8547-530: The hot, dry, and dusty trade wind known as the Harmattan . The southern regions have a more equatorial climate, but they are subject to desertification , while the extreme northeast regions of the country are a steppe . In the southwest, the Dzanga-Sangha National Park is located in a rain forest area. The country is noted for its population of forest elephants and western lowland gorillas . In

8658-646: The late 19th century during the Scramble for Africa . Europeans, primarily the French, Germans , and Belgians , arrived in the area in 1885. France seized and colonized Ubangi-Shari territory in 1894. In 1911 at the Treaty of Fez , France ceded a nearly 300,000 km portion of the Sangha and Lobaye basins to the German Empire which ceded a smaller area (in present-day Chad ) to France. After World War I France again annexed

8769-452: The liberation of political prisoners, the integration of FDPC into government, an amnesty for the UFDR , its recognition as a political party, and the integration of its fighters into the national army. Several groups continued to fight but other groups signed on to the agreement or similar agreements with the government (e.g., UFR on 15 December 2008). The only major group not to sign an agreement at

8880-542: 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

8991-411: 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

9102-554: The north, the Manovo-Gounda St Floris National Park is well-populated with wildlife, including leopards , lions , cheetahs and rhinos , and the Bamingui-Bangoran National Park is located in the northeast of the Central African Republic. The parks have been seriously affected by the activities of poachers, particularly those from Sudan , over the past two decades. Gold Gold

9213-709: The official party of the state. On 31 December 1965, Dacko was overthrown in the Saint-Sylvestre coup d'état by Colonel Jean-Bédel Bokassa , who suspended the constitution and dissolved the National Assembly. President Bokassa declared himself President for Life in 1972 and named himself Emperor Bokassa I of the Central African Empire (as the country was renamed) on 4 December 1976. A year later, Emperor Bokassa crowned himself in an expensive ceremony. In April 1979, young students protested against Bokassa's decree that all school pupils were required to buy uniforms from

9324-563: 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

9435-442: The press and freedom of movement. Despite its significant mineral deposits and other resources, such as uranium reserves, crude oil , gold , diamonds , cobalt , lumber , and hydropower , as well as significant quantities of arable land , the Central African Republic is among the ten poorest countries in the world, with the lowest GDP per capita at purchasing power parity in the world as of 2017. As of 2022 , according to

9546-459: 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

9657-681: 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

9768-620: 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

9879-420: 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

9990-935: 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

10101-464: 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

10212-474: 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

10323-486: 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

10434-446: 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,

10545-436: 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

10656-474: The territory. Modeled on King Leopold 's Congo Free State , concessions were doled out to private companies that endeavored to strip the region's assets as quickly and cheaply as possible before depositing a percentage of their profits into the French treasury. The concessionary companies forced local people to harvest rubber, coffee, and other commodities without pay and held their families hostage until they met their quotas. In 1920, French Equatorial Africa

10767-482: The time was the CPJP , which continued its activities and signed a peace agreement with the government on 25 August 2012. In 2011, Bozizé was reelected in an election which was widely considered fraudulent. In November 2012, Séléka , a coalition of rebel groups, took over towns in the northern and central regions of the country. These groups eventually reached a peace deal with Bozizé's government in January 2013, involving

10878-403: 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

10989-574: The upper hand by bringing in at least 300 troops of the Congolese rebel leader Jean-Pierre Bemba and Libyan soldiers. In the aftermath of the failed coup , militias loyal to Patassé sought revenge against rebels in many neighborhoods of Bangui and incited unrest including the murder of many political opponents. Eventually, Patassé came to suspect that General François Bozizé was involved in another coup attempt against him, which led Bozizé to flee with loyal troops to Chad. In March 2003, Bozizé launched

11100-410: The use of boats, allowed for the transportation of goods. Products were often moved in ceramic pots. The Bouar Megaliths in the western region of the country indicate an advanced level of habitation dating back to the very late Neolithic Era ( c.  3500–2700 BCE ). Ironwork developed in the region around 1000   BCE. The Ubangian people settled along the Ubangi River in what

11211-417: 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

11322-457: The vote, a second round of elections was held on 14 February 2016 with run-offs on 31 March 2016. In the second round of voting, former Prime Minister Faustin-Archange Touadéra was declared the winner with 63% of the vote, defeating Union for Central African Renewal candidate Anicet-Georges Dologuélé , another former Prime Minister. While the elections suffered from many potential voters being absent as they had taken refuge in other countries,

11433-438: The year, there were international warnings of a "genocide" and fighting was largely reprisal attacks on civilians by Seleka's predominantly Muslim fighters and Christian militias called " anti-balaka ". By August 2013, there were reports of over 200,000 internally displaced persons (IDPs). French President François Hollande called on the UN Security Council and the African Union to increase their efforts to stabilize

11544-783: 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

11655-639: Was again overthrown in a coup by General André Kolingba on 1 September 1981. Kolingba suspended the constitution and ruled with a military junta until 1985. He introduced a new constitution in 1986 which was adopted by a nationwide referendum. Membership in his new party, the Rassemblement Démocratique Centrafricain (RDC), was voluntary. In 1987 and 1988, semi-free elections to parliament were held, but Kolingba's two major political opponents, Abel Goumba and Ange-Félix Patassé , were not allowed to participate. By 1990, inspired by

11766-555: Was elected interim president by the National Transitional Council, becoming the first ever female Central African president. On 23 July 2014, following Congolese mediation efforts, Séléka and anti-balaka representatives signed a ceasefire agreement in Brazzaville . By the end of 2014, the country was de facto partitioned with the anti-Balaka in the southwest and ex-Seleka in the northeast. In March 2015, Samantha Power ,

11877-414: Was established and Ubangi-Shari was administered from Brazzaville . During the 1920s and 1930s the French introduced a policy of mandatory cotton cultivation, a network of roads were built, attempts were made to combat sleeping sickness , and Protestant missions were established to spread Christianity. New forms of forced labour were also introduced and a large number of Ubangians were sent to work on

11988-438: Was later removed by General François Bozizé in a 2003 coup . The Central African Republic Bush War began in 2004 and, despite a peace treaty in 2007 and another in 2011, civil war resumed in 2012. The civil war perpetuated the country's poor human rights record : it was characterized by widespread and increasing abuses by various participating armed groups, such as arbitrary imprisonment, torture, and restrictions on freedom of

12099-659: Was perhaps the largest anti-colonial rebellion in Africa during the interwar years, was carefully hidden from the French public because it provided evidence of strong opposition to French colonial rule and forced labour. French colonization in Oubangui-Chari is considered to be the most brutal of the French colonial Empire. In September 1940, during the Second World War , pro-Gaullist French officers took control of Ubangi-Shari and General Leclerc established his headquarters for

12210-469: Was rejected by the Constitutional Court of the country, which held that Bozizé did not satisfy the "good morality" requirement for candidates because of an international warrant and United Nations sanctions against him for alleged assassinations, torture and other crimes. As large parts of the country were at the time controlled by armed groups, the election could not be conducted in many areas of

12321-605: 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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