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Banks Setlhodi

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99-712: Motsau Joseph "Banks" Setlhodi (born 12 April 1947) in Randfontein , South Africa is a retired South African association football player who played in South Africa for Randfontein Young Zebras and Kaizer Chiefs . Setlhodi grew up in Madubaville, Randfontein . He attended Topia Lower Primary and later Wesele Higher Primary. He grew up playing soccer in the street until he was invited by his friend to play for Randfontein Young Zebras' 3rd Division side which he played for until he

198-431: A nuclear reactor . Another fissile isotope, uranium-233 , can be produced from natural thorium and is studied for future industrial use in nuclear technology. Uranium-238 has a small probability for spontaneous fission or even induced fission with fast neutrons; uranium-235, and to a lesser degree uranium-233, have a much higher fission cross-section for slow neutrons. In sufficient concentration, these isotopes maintain

297-598: A 2013 Ookla Net Index report, it was found that Randfontein has the fastest broadband access in South Africa. Randfontein has a download speed of 10 Mbit/s, followed by Bryanston , Midrand and Randburg , which are also all in the Gauteng province. Shopping in Randfontein is characterized by typical High Street shopping with the majority of the shops situated along Main Reef Road and surrounds. The main mall, Village Square,

396-524: A description of this process of reactor control). As little as 15 lb (6.8 kg) of uranium-235 can be used to make an atomic bomb. The nuclear weapon detonated over Hiroshima , called Little Boy , relied on uranium fission. However, the first nuclear bomb (the Gadget used at Trinity ) and the bomb that was detonated over Nagasaki ( Fat Man ) were both plutonium bombs. Uranium metal has three allotropic forms: The major application of uranium in

495-471: A distribution of uranium oxidation species in various forms ranging from most oxidized to least oxidized. Particles with short residence times in a calciner will generally be less oxidized than those with long retention times or particles recovered in the stack scrubber. Uranium content is usually referenced to U 3 O 8 , which dates to the days of the Manhattan Project when U 3 O 8

594-556: A form of invisible light or rays emitted by uranium had exposed the plate. During World War I when the Central Powers suffered a shortage of molybdenum to make artillery gun barrels and high speed tool steels, they routinely used ferrouranium alloy as a substitute, as it presents many of the same physical characteristics as molybdenum. When this practice became known in 1916 the US government requested several prominent universities to research

693-727: A higher incidence of cancer . An excess risk of lung cancer among Navajo uranium miners, for example, has been documented and linked to their occupation. The Radiation Exposure Compensation Act , a 1990 law in the US, required $ 100,000 in "compassion payments" to uranium miners diagnosed with cancer or other respiratory ailments. During the Cold War between the Soviet Union and the United States, huge stockpiles of uranium were amassed and tens of thousands of nuclear weapons were created using enriched uranium and plutonium made from uranium. After

792-448: A much more complicated and far more powerful type of fission/fusion bomb ( thermonuclear weapon ) was built, that uses a plutonium-based device to cause a mixture of tritium and deuterium to undergo nuclear fusion . Such bombs are jacketed in a non-fissile (unenriched) uranium case, and they derive more than half their power from the fission of this material by fast neutrons from the nuclear fusion process. The main use of uranium in

891-519: A municipality in 1929. Apart from having the largest stamp mill in the world, Randfontein, like many of the other outlying areas of Johannesburg, is essentially a rural collection of farms and small holdings in a particularly beautiful part of Gauteng. Randfontein's existence dates back to the 1550s when the AmaNdebele lived as one nation at Emhlangeni (today's Randfontein area) under King Mhlanga approximately between 1550 and 1580. The name of Emhlangeni

990-459: A plutonium-based device (see Trinity test and " Fat Man ") whose plutonium was derived from uranium-238. Little Boy became the first nuclear weapon used in war when it was detonated over Hiroshima , Japan , on 6 August 1945. Exploding with a yield equivalent to 12,500 tonnes of TNT , the blast and thermal wave of the bomb destroyed nearly 50,000 buildings and killed about 75,000 people (see Atomic bombings of Hiroshima and Nagasaki ). Initially it

1089-547: A population of 149,286, which incorporates Mohlakeng and Toekomsrus. (In 2001, the population was 128,731.) The average elevation of the town is 1709m above sea level . The total municipal area, after recent restructuring, is 475 km (183 sq mi). According to the Randfontein Socio-Economic Survey of 2006, Randfontein's population is divided into Black (79.2%), White (10.6%), Coloured (10.1%), and Asian/Indian (0.1%). The local immigrant population

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1188-405: A reaction by piling together 360 tonnes of graphite , 53 tonnes of uranium oxide , and 5.5 tonnes of uranium metal, most of which was supplied by Westinghouse Lamp Plant in a makeshift production process. Two types of atomic bomb were developed by the United States during World War II : a uranium-based device (codenamed " Little Boy ") whose fissile material was highly enriched uranium , and

1287-413: A shielding material. Due to its high density, this material is found in inertial guidance systems and in gyroscopic compasses . Depleted uranium is preferred over similarly dense metals due to its ability to be easily machined and cast as well as its relatively low cost. The main risk of exposure to depleted uranium is chemical poisoning by uranium oxide rather than radioactivity (uranium being only

1386-525: A shorter half-life and so is an extinct radionuclide , having long since decayed completely to Th. Further uranium-236 was produced by the decay of Pu , accounting for the observed higher-than-expected abundance of thorium and lower-than-expected abundance of uranium. While the natural abundance of uranium has been supplemented by the decay of extinct Pu (half-life 375,000 years) and Cm (half-life 16 million years), producing U and U respectively, this occurred to an almost negligible extent due to

1485-494: A sustained nuclear chain reaction . This generates the heat in nuclear power reactors and produces the fissile material for nuclear weapons. The primary civilian use for uranium harnesses the heat energy to produce electricity. Depleted uranium ( U) is used in kinetic energy penetrators and armor plating . The 1789 discovery of uranium in the mineral pitchblende is credited to Martin Heinrich Klaproth , who named

1584-778: A warm friendship which has led to rumours that the Kruger Millions (millions of gold coins minted for the Zuid Afrikaanse Republiek, or the South African Republic ) were buried in the Homestead's grounds to stop them from falling into British hands during the Second Boer War . The Homestead is the home that Robinson lived in which is now situated along Homestead Avenue next to Riebeeck Lake and owned by well-known local businessman and racing driver, Ben Morgenrood. Over

1683-412: A weak alpha emitter ). During the later stages of World War II , the entire Cold War , and to a lesser extent afterwards, uranium-235 has been used as the fissile explosive material to produce nuclear weapons. Initially, two major types of fission bombs were built: a relatively simple device that uses uranium-235 and a more complicated mechanism that uses plutonium-239 derived from uranium-238. Later,

1782-530: A world total production of 48,332 tonnes. Most uranium was produced not by conventional underground mining of ores (29% of production), but by in situ leaching (66%). In the late 1960s, UN geologists discovered major uranium deposits and other rare mineral reserves in Somalia . The find was the largest of its kind, with industry experts estimating the deposits at over 25% of the world's then known uranium reserves of 800,000 tons. The ultimate available supply

1881-552: Is malleable , ductile , slightly paramagnetic , strongly electropositive and a poor electrical conductor . Uranium metal has a very high density of 19.1 g/cm , denser than lead (11.3 g/cm ), but slightly less dense than tungsten and gold (19.3 g/cm ). Uranium metal reacts with almost all non-metallic elements (except noble gases ) and their compounds , with reactivity increasing with temperature. Hydrochloric and nitric acids dissolve uranium, but non-oxidizing acids other than hydrochloric acid attack

1980-589: Is a gold mining town in the West Rand , Gauteng , South Africa, 40 km (25 mi) west of Johannesburg . With the Witwatersrand gold rush in full swing, mining financier JB Robinson bought the farm Randfontein and, in 1889, floated the Randfontein Estates Gold Mining Company. The town was established in 1890 to serve the new mine and was administered by Krugersdorp until it became

2079-519: Is a naturally occurring element found in low levels in all rock, soil, and water. It is the highest-numbered element found naturally in significant quantities on Earth and is almost always found combined with other elements. Uranium is the 48th most abundant element in the Earth’s crust. The decay of uranium, thorium , and potassium-40 in Earth's mantle is thought to be the main source of heat that keeps

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2178-589: Is a silvery-grey metal in the actinide series of the periodic table . A uranium atom has 92 protons and 92 electrons , of which 6 are valence electrons . Uranium radioactively decays , usually by emitting an alpha particle . The half-life of this decay varies between 159,200 and 4.5 billion years for different isotopes , making them useful for dating the age of the Earth . The most common isotopes in natural uranium are uranium-238 (which has 146 neutrons and accounts for over 99% of uranium on Earth) and uranium-235 (which has 143 neutrons). Uranium has

2277-548: Is also a private hospital and was initially focused on mine-related illnesses and diseases but has subsequently become a general private hospital. In July 2013, it was renovated and renamed the Lenmed Health Randfontein Private Hospital. Most road signs call it just Randfontein Private Hospital. Uranium Uranium is a chemical element with the symbol U and atomic number 92. It

2376-577: Is also along the main street and provides comfortable access to 72 shops (GLA approximately 20,500m ). Other centres around town include: Randfontein Station Mall (20 shops) and Greenhills Spar Centre (20 shops). Numerous shops are also found along Randgate's main street, Union Street. The proposed Lakeview Mall was abandoned due to a lack of funding. However, this development was replaced by the new Tambotie Mall (initially 20,000m ) with anchor tenants Checkers, Woolworths (Foods and Fashion), and Dischem, under

2475-519: Is also fissile by thermal neutrons. These discoveries led numerous countries to begin working on the development of nuclear weapons and nuclear power . Despite fission having been discovered in Germany, the Uranverein ("uranium club") Germany's wartime project to research nuclear power and/or weapons was hampered by limited resources, infighting, the exile or non-involvement of several prominent scientists in

2574-643: Is an annual event that was first held in February 1987 and is now held in February/March of each year. The largest show of its kind in western Gauteng, it plays host to live entertainment, family fun, and many things to taste, see and do. The Randfontein Show is the fifth largest event of its kind in South Africa and reaches attendances of over 110,000 annually. The show takes place at the Greenhills Sport Stadium to

2673-531: Is being built. A few factories sell directly to the public where goods can be obtained at greatly reduced prices. Some of these include: The West Rand of Gauteng is a particularly pretty part of the province flanked to the west by the Magaliesburg mountain range and to the northwest the Cradle of Humankind. Places of interest and of noteworthy historical value in the immediate vicinity include: The Randfontein Show

2772-520: Is believed to be sufficient for at least the next 85 years, though some studies indicate underinvestment in the late twentieth century may produce supply problems in the 21st century. Uranium deposits seem to be log-normal distributed. There is a 300-fold increase in the amount of uranium recoverable for each tenfold decrease in ore grade. In other words, there is little high grade ore and proportionately much more low grade ore available. Calcined uranium yellowcake, as produced in many large mills, contains

2871-781: Is difficult to precipitate uranium as phosphate in the presence of excess carbonate at alkaline pH. A Sphingomonas sp. strain BSAR-1 has been found to express a high activity alkaline phosphatase (PhoK) that has been applied for bioprecipitation of uranium as uranyl phosphate species from alkaline solutions. The precipitation ability was enhanced by overexpressing PhoK protein in E. coli . Plants absorb some uranium from soil. Dry weight concentrations of uranium in plants range from 5 to 60 parts per billion, and ash from burnt wood can have concentrations up to 4 parts per million. Dry weight concentrations of uranium in food plants are typically lower with one to two micrograms per day ingested through

2970-418: Is diluted with uranium-238 and reused as fuel for nuclear reactors. Spent nuclear fuel forms radioactive waste , which mostly consists of uranium-238 and poses a significant health threat and environmental impact . Uranium is a silvery white, weakly radioactive metal . It has a Mohs hardness of 6, sufficient to scratch glass and roughly equal to that of titanium , rhodium , manganese and niobium . It

3069-485: Is found in hundreds of minerals, including uraninite (the most common uranium ore ), carnotite , autunite , uranophane , torbernite , and coffinite . Significant concentrations of uranium occur in some substances such as phosphate rock deposits, and minerals such as lignite , and monazite sands in uranium-rich ores (it is recovered commercially from sources with as little as 0.1% uranium ). Like all elements with atomic weights higher than that of iron , uranium

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3168-524: Is made up mainly of Mozambiquans (Portuguese), Angolans (Portuguese), Malawians (Chichewa), Ethiopians (Amharic), and Chinese (Chinese). A fair portion of shops in the CBD are run by Ethiopians and Chinese. Randfontein differs slightly from other parts of the West Rand, in that it is slightly female dominant (50.6%). This trend is throughout the gender structure with the exception of the age group younger than 14 which

3267-427: Is only naturally formed by the r-process (rapid neutron capture) in supernovae and neutron star mergers . Primordial thorium and uranium are only produced in the r-process, because the s-process (slow neutron capture) is too slow and cannot pass the gap of instability after bismuth. Besides the two extant primordial uranium isotopes, U and U, the r-process also produced significant quantities of U , which has

3366-407: Is produced through the thermal decomposition of uranium halides on a hot filament. It is estimated that 6.1 million tonnes of uranium exists in ores that are economically viable at US$ 130 per kg of uranium, while 35 million tonnes are classed as mineral resources (reasonable prospects for eventual economic extraction). Australia has 28% of the world's known uranium ore reserves and

3465-547: Is served by two international airports, namely the OR Tambo International Airport in Kempton Park 80 km (50 mi) to the east and Lanseria International Airport 41 km (25 mi) north-east. The main national Johannesburg / Cape Town railway line cuts through Randfontein although the daily train does not stop at the Randfontein station. This line also doubles as the metro rail line which serves

3564-404: Is slightly male dominant. The working age-group (15 to 64) is the largest and makes up 65.5% of the local population. The elderly group (above 65 of age) constitutes only 6.1% of the population. During apartheid , Randfontein was mostly Afrikaner . The racial makeup and language distribution changed dramatically from the 2001 census to the 2011 census. The Black population grew from around 16% of

3663-448: Is the only naturally occurring fissile isotope , which makes it widely used in nuclear power plants and nuclear weapons . However, because of the low abundance of uranium-235 in natural uranium (which is, overwhelmingly, mostly uranium-238), uranium needs to undergo enrichment so that enough uranium-235 is present. Uranium-238 is fissionable by fast neutrons and is fertile , meaning it can be transmuted to fissile plutonium-239 in

3762-441: Is then calcined to remove impurities from the milling process before refining and conversion. Commercial-grade uranium can be produced through the reduction of uranium halides with alkali or alkaline earth metals . Uranium metal can also be prepared through electrolysis of KUF 5 or UF 4 , dissolved in molten calcium chloride ( CaCl 2 ) and sodium chloride ( Na Cl) solution. Very pure uranium

3861-513: Is translated today into the Sesotho language as Mohlakeng, which is one of the southeastern suburbs of the town. Randfontein was established formally on 3 March 1890 and proclaimed a municipality in 1929. Some important dates in Randfontein's history: Remnants of the Jameson Raid (29 December 1895 – 2 January 1896) can be found in Randfontein. Various graves of those killed are scattered around

3960-585: Is used for X-ray targets in the making of high-energy X-rays. The use of pitchblende , uranium in its natural oxide form, dates back to at least the year 79 AD, when it was used in the Roman Empire to add a yellow color to ceramic glazes. Yellow glass with 1% uranium oxide was found in a Roman villa on Cape Posillipo in the Bay of Naples , Italy, by R. T. Gunther of the University of Oxford in 1912. Starting in

4059-402: The Manhattan Project , another team led by Enrico Fermi was able to initiate the first artificial self-sustained nuclear chain reaction , Chicago Pile-1 . An initial plan using enriched uranium-235 was abandoned as it was as yet unavailable in sufficient quantities. Working in a lab below the stands of Stagg Field at the University of Chicago , the team created the conditions needed for such

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4158-492: The Megatons to Megawatts Program . An additional 4.6 billion tonnes of uranium are estimated to be dissolved in sea water ( Japanese scientists in the 1980s showed that extraction of uranium from sea water using ion exchangers was technically feasible). There have been experiments to extract uranium from sea water, but the yield has been low due to the carbonate present in the water. In 2012, ORNL researchers announced

4257-466: The Oklo Fossil Reactors . The ore deposit is 1.7 billion years old; then, uranium-235 constituted about 3% of uranium on Earth. This is high enough to permit a sustained chain reaction, if other supporting conditions exist. The capacity of the surrounding sediment to contain the health-threatening nuclear waste products has been cited by the U.S. federal government as supporting evidence for

4356-688: The Shippingport Atomic Power Station in Pennsylvania , which began on 26 May 1958. Nuclear power was used for the first time for propulsion by a submarine , the USS Nautilus , in 1954. In 1972, French physicist Francis Perrin discovered fifteen ancient and no longer active natural nuclear fission reactors in three separate ore deposits at the Oklo mine in Gabon , Africa, collectively known as

4455-520: The United States (2.5%), Argentina (2.1%) and Ukraine (1.9%). In 2008, Kazakhstan was forecast to increase production and become the world's largest supplier of uranium by 2009; Kazakhstan has dominated the world's uranium market since 2010. In 2021, its share was 45.1%, followed by Namibia (11.9%), Canada (9.7%), Australia (8.7%), Uzbekistan (7.2%), Niger (4.7%), Russia (5.5%), China (3.9%), India (1.3%), Ukraine (0.9%), and South Africa (0.8%), with

4554-520: The Witwatersrand between Randfontein in the west and Springs in the east, a road distance of about 87 km (54 mi). Two primary hospitals serve the Randfontein area, Robinson Hospital and Sir Albert Medical Centre. Robinson Hospital (Hospital Street) is a private hospital and part of the Lifecare Health group. The hospital boasts 109 beds and 4 theatres with a 24-hour accident and emergency unit. Sir Albert Medical Centre (Ward Street Extension)

4653-592: The break-up of the Soviet Union in 1991, an estimated 600 short tons (540 metric tons) of highly enriched weapons grade uranium (enough to make 40,000 nuclear warheads) had been stored in often inadequately guarded facilities in the Russian Federation and several other former Soviet states. Police in Asia , Europe , and South America on at least 16 occasions from 1993 to 2005 have intercepted shipments of smuggled bomb-grade uranium or plutonium, most of which

4752-499: The first nuclear weapon used in war . An ensuing arms race during the Cold War between the United States and the Soviet Union produced tens of thousands of nuclear weapons that used uranium metal and uranium-derived plutonium-239 . Dismantling of these weapons and related nuclear facilities is carried out within various nuclear disarmament programs and costs billions of dollars. Weapon-grade uranium obtained from nuclear weapons

4851-432: The oceans may contain 10  kg (2 × 10  lb). The concentration of uranium in soil ranges from 0.7 to 11 parts per million (up to 15 parts per million in farmland soil due to use of phosphate fertilizers ), and its concentration in sea water is 3 parts per billion. Uranium is more plentiful than antimony , tin , cadmium , mercury , or silver, and it is about as abundant as arsenic or molybdenum . Uranium

4950-727: The 1960s mining in the area came to a virtual standstill, but in the 1970s new gold deposits were discovered to the south of Randfontein and the Cooke Section was opened up in 1976. Cooke Section produced gold and uranium, the uranium being used for the Koeberg Nuclear Power Station in the Western Cape . Randfontein Estates had the largest stamp mill in the world, with 600 stamps. A large industrial area, Aureus, serves greater Randfontein and many industries are scattered throughout

5049-510: The CBD). The climate here is mild in winter (sunny clear days and cold nights), and generally warm and wet in summer, dominated by thunderstorms. When compared with winter, the summers have much more rainfall. This location is classified as Cwb by Köppen and Geiger (dry winter, subtropical highland climate). The average annual temperature is 16.1 °C (61.0 °F). The rainfall average is 794 mm (31.3 in) per year. As of 2011, Randfontein has

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5148-619: The Dean of the Sapienza University of Rome , Orso Mario Corbino , named ausenium and hesperium , respectively. The experiments leading to the discovery of uranium's ability to fission (break apart) into lighter elements and release binding energy were conducted by Otto Hahn and Fritz Strassmann in Hahn's laboratory in Berlin. Lise Meitner and her nephew, physicist Otto Robert Frisch , published

5247-408: The Earth's outer core in the liquid state and drives mantle convection , which in turn drives plate tectonics . Uranium's concentration in the Earth's crust is (depending on the reference) 2 to 4 parts per million, or about 40 times as abundant as silver . The Earth's crust from the surface to 25 km (15 mi) down is calculated to contain 10  kg (2 × 10  lb) of uranium while

5346-524: The Robinson Deep gold mine. The lake has a pH of 2.6. Water has a natural uranium concentration of 0.0004 mg/L. The Department of Water and Sanitation considers a concentration of 0.07 mg/L safe to drink. Robinson Lake has a uranium concentration of 16 mg/L which is more than 220 times safe levels. This has resulted in Robinson Lake being declared a radioactive area and it is closed off to

5445-686: The Russian government approved a federal program for nuclear and radiation safety for 2016 to 2030 with a budget of 562 billion rubles (ca. 8 billion USD ). Its key issue is "the deferred liabilities accumulated during the 70 years of the nuclear industry, particularly during the time of the Soviet Union". About 73% of the budget will be spent on decommissioning aged and obsolete nuclear reactors and nuclear facilities, especially those involved in state defense programs; 20% will go in processing and disposal of nuclear fuel and radioactive waste, and 5% into monitoring and ensuring of nuclear and radiation safety. Uranium

5544-656: The West Rand. In Randfontein, the graves of troopers William Charles Beatty-Powell, John Bernard Bletsoe, Harry Davies, John Foster, and C.E. Hennessy, are hidden amongst the trees in what was originally known as the Randfontein Estates Gold Mine Military Cemetery. The graves are beside the railway line diagonally opposite where Uncle Harry's Roadhouse is currently located at the northern entrance to town from Krugersdorp. Randfontein War Memorial: This really pretty memorial can be found next to

5643-444: The bigger centres they are relatively efficient and used by members of the public from far afield. The R28 is a regional route connecting Krugersdorp with Vereeniging that passes through Randfontein (called Main Reef Road through central Randfontein) while the R41 connects Randfontein with Johannesburg . The R559 connects Randfontein with Carletonville and Lenasia . Randfontein

5742-566: The bulk of the use, including common bathroom and kitchen tiles which can be produced in green, yellow, mauve , black, blue, red and other colors. Uranium was also used in photographic chemicals (especially uranium nitrate as a toner ), in lamp filaments for stage lighting bulbs, to improve the appearance of dentures , and in the leather and wood industries for stains and dyes. Uranium salts are mordants of silk or wool. Uranyl acetate and uranyl formate are used as electron-dense "stains" in transmission electron microscopy , to increase

5841-511: The centre opened.) Another shopping centre, Umphakathi Mall (12,500m ), opened on 29 April 2021. This is bordered by the R28, R559, and Ralerata Street between Randfontein Central/Toekomsrus and Mohlakeng. The inclusion of a new taxi rank and a filling station will attract critical mass by creating a prominent transport node, and limiting the shopping outflow. A residential phase around the complex

5940-409: The civilian sector is to fuel nuclear power plants . One kilogram of uranium-235 can theoretically produce about 20  terajoules of energy (2 × 10   joules ), assuming complete fission; as much energy as 1.5 million kilograms (1,500 tonnes ) of coal . Commercial nuclear power plants use fuel that is typically enriched to around 3% uranium-235. The CANDU and Magnox designs are

6039-549: The contrast of biological specimens in ultrathin sections and in negative staining of viruses , isolated cell organelles and macromolecules . The discovery of the radioactivity of uranium ushered in additional scientific and practical uses of the element. The long half-life of uranium-238 (4.47 × 10 years) makes it well-suited for use in estimating the age of the earliest igneous rocks and for other types of radiometric dating , including uranium–thorium dating , uranium–lead dating and uranium–uranium dating . Uranium metal

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6138-442: The development of uranium mining to extract the radium, which was used to make glow-in-the-dark paints for clock and aircraft dials. This left a prodigious quantity of uranium as a waste product, since it takes three tonnes of uranium to extract one gram of radium. This waste product was diverted to the glazing industry, making uranium glazes very inexpensive and abundant. Besides the pottery glazes, uranium tile glazes accounted for

6237-465: The element very slowly. When finely divided, it can react with cold water; in air, uranium metal becomes coated with a dark layer of uranium oxide . Uranium in ores is extracted chemically and converted into uranium dioxide or other chemical forms usable in industry. Uranium-235 was the first isotope that was found to be fissile . Other naturally occurring isotopes are fissionable, but not fissile. On bombardment with slow neutrons, uranium-235 most of

6336-486: The feasibility to store spent nuclear fuel at the Yucca Mountain nuclear waste repository . Above-ground nuclear tests by the Soviet Union and the United States in the 1950s and early 1960s and by France into the 1970s and 1980s spread a significant amount of fallout from uranium daughter isotopes around the world. Additional fallout and pollution occurred from several nuclear accidents . Uranium miners have

6435-498: The field and several crucial mistakes such as failing to account for impurities in available graphite samples which made it appear less suitable as a neutron moderator than it is in reality. Germany's attempts to build a natural uranium / heavy water reactor had not come close to reaching criticality by the time the Americans reached Haigerloch , the site of the last German wartime reactor experiment. On 2 December 1942, as part of

6534-464: The first sample of uranium metal by heating uranium tetrachloride with potassium . Henri Becquerel discovered radioactivity by using uranium in 1896. Becquerel made the discovery in Paris by leaving a sample of a uranium salt, K 2 UO 2 (SO 4 ) 2 (potassium uranyl sulfate), on top of an unexposed photographic plate in a drawer and noting that the plate had become "fogged". He determined that

6633-499: The fissile component, and on 29 February 1940, Nier used an instrument he built at the University of Minnesota to separate the world's first uranium-235 sample in the Tate Laboratory. Using Columbia University 's cyclotron , John Dunning confirmed the sample to be the isolated fissile material on 1 March. Further work found that the far more common uranium-238 isotope can be transmuted into plutonium, which, like uranium-235,

6732-605: The food people eat. Worldwide production of uranium in 2021 was 48,332 tonnes , of which 21,819 t (45%) was mined in Kazakhstan . Other important uranium mining countries are Namibia (5,753 t), Canada (4,693 t), Australia (4,192 t), Uzbekistan (3,500 t), and Russia (2,635 t). Uranium ore is mined in several ways: open pit , underground , in-situ leaching , and borehole mining . Low-grade uranium ore mined typically contains 0.01 to 0.25% uranium oxides. Extensive measures must be employed to extract

6831-448: The highest atomic weight of the primordially occurring elements. Its density is about 70% higher than that of lead and slightly lower than that of gold or tungsten . It occurs naturally in low concentrations of a few parts per million in soil, rock and water, and is commercially extracted from uranium-bearing minerals such as uraninite . Many contemporary uses of uranium exploit its unique nuclear properties. Uranium-235

6930-703: The late Middle Ages , pitchblende was extracted from the Habsburg silver mines in Joachimsthal , Bohemia (now Jáchymov in the Czech Republic) in the Ore Mountains , and was used as a coloring agent in the local glassmaking industry. In the early 19th century, the world's only known sources of uranium ore were these mines. The discovery of the element is credited to the German chemist Martin Heinrich Klaproth . While he

7029-501: The management of Broll. This shopping centre is on the corner of Tambotie and Malan streets, around the southern end of Riebeeck Lake. Excavation and groundworks started in February 2016 and it opened to the public on 27 April 2017. Municipal proposals for this precinct include a housing development and a new office park to be developed later. (The first recorded armed robbery occurred at the Dischem on Friday 7 July 2017, just three months after

7128-588: The metal from its ore. High-grade ores found in Athabasca Basin deposits in Saskatchewan , Canada can contain up to 23% uranium oxides on average. Uranium ore is crushed and rendered into a fine powder and then leached with either an acid or alkali . The leachate is subjected to one of several sequences of precipitation, solvent extraction, and ion exchange. The resulting mixture, called yellowcake , contains at least 75% uranium oxides U 3 O 8 . Yellowcake

7227-491: The military sector is in high-density penetrators. This ammunition consists of depleted uranium (DU) alloyed with 1–2% other elements, such as titanium or molybdenum . At high impact speed, the density, hardness, and pyrophoricity of the projectile enable the destruction of heavily armored targets. Tank armor and other removable vehicle armor can also be hardened with depleted uranium plates. The use of depleted uranium became politically and environmentally contentious after

7326-527: The municipal area including the more rural areas. Notable industries, in addition to those related to mining, include the following: Nola (dog food, mayonnaise, sandwich spread, cooking oil), Tiger Brands (butter, peanut butter), and Aranda (blankets for the hotel industry and home use). Aranda Textile Mills (Pty) Ltd is a fourth generation Italian owned family business and has been producing quality blankets and throws since 1951. Their blankets can be seen in most hotels in South Africa. A factory shop, open to

7425-456: The new element after the recently discovered planet Uranus . Eugène-Melchior Péligot was the first person to isolate the metal, and its radioactive properties were discovered in 1896 by Henri Becquerel . Research by Otto Hahn , Lise Meitner , Enrico Fermi and others, such as J. Robert Oppenheimer starting in 1934 led to its use as a fuel in the nuclear power industry and in Little Boy ,

7524-570: The newly discovered metal itself (in fact, that powder was an oxide of uranium ). He named the newly discovered element after the planet Uranus (named after the primordial Greek god of the sky ), which had been discovered eight years earlier by William Herschel . In 1841, Eugène-Melchior Péligot , Professor of Analytical Chemistry at the Conservatoire National des Arts et Métiers (Central School of Arts and Manufactures) in Paris , isolated

7623-650: The only commercial reactors capable of using unenriched uranium fuel. Fuel used for United States Navy reactors is typically highly enriched in uranium-235 (the exact values are classified ). In a breeder reactor , uranium-238 can also be converted into plutonium-239 through the following reaction: Before (and, occasionally, after) the discovery of radioactivity, uranium was primarily used in small amounts for yellow glass and pottery glazes, such as uranium glass and in Fiestaware . The discovery and isolation of radium in uranium ore (pitchblende) by Marie Curie sparked

7722-431: The physical explanation in February 1939 and named the process " nuclear fission ". Soon after, Fermi hypothesized that fission of uranium might release enough neutrons to sustain a fission reaction. Confirmation of this hypothesis came in 1939, and later work found that on average about 2.5 neutrons are released by each fission of uranium-235. Fermi urged Alfred O. C. Nier to separate uranium isotopes for determination of

7821-557: The possibility that these organisms could be used in bioremediation to decontaminate uranium-polluted water. The proteobacterium Geobacter has also been shown to bioremediate uranium in ground water. The mycorrhizal fungus Glomus intraradices increases uranium content in the roots of its symbiotic plant. In nature, uranium(VI) forms highly soluble carbonate complexes at alkaline pH. This leads to an increase in mobility and availability of uranium to groundwater and soil from nuclear wastes which leads to health hazards. However, it

7920-512: The public, is located on the grounds of the factory in Homelake. Shutterlock was established in Randfontein in 1987, the company manufactures, supplies and imports safety critical lifting and rigging equipment including mine winding rope to the mining industry in South Africa as well as SADC countries. Other large national companies have their head offices, or main branches, in Randfontein: In

8019-464: The public. The general consensus is that this has been caused by acid mine drainage . It is also however now a dangerous area and nothing is being done about the number of people accessing it. Randfontein lies at 1,709 m above mean sea level. (By comparison, Johannesburg is at 1,733 m AMSL at the entrance to the Carlton Centre in the CBD, and Pretoria is 1,320 m AMSL in the middle of Church Square in

8118-545: The roadhouse on the corner of Randfontein and Main Reef Roads, Surprisingly the components of the memorial are all in a reasonably good condition and it is fenced off. On 11 June 2015, a hidden graveyard with about 80 to 100 graves dating back to the 1800s was discovered near the grain silos off Main Reef Road. It's not known yet whether these are connected to the graves of the Jameson Raid. Paul Kruger and JB Robinson enjoyed

8217-541: The shorter half-lives of these parents and their lower production than U and Pu, the parents of thorium: the Cm/ U ratio at the formation of the Solar System was (7.0 ± 1.6) × 10 . Some bacteria, such as Shewanella putrefaciens , Geobacter metallireducens and some strains of Burkholderia fungorum , use uranium for their growth and convert U(VI) to U(IV). Recent research suggests that this pathway includes reduction of

8316-509: The soluble U(VI) via an intermediate U(V) pentavalent state. Other organisms, such as the lichen Trapelia involuta or microorganisms such as the bacterium Citrobacter , can absorb concentrations of uranium that are up to 300 times the level of their environment. Citrobacter species absorb uranyl ions when given glycerol phosphate (or other similar organic phosphates). After one day, one gram of bacteria can encrust themselves with nine grams of uranyl phosphate crystals; this creates

8415-496: The stabilization of political and economical turmoil of the early 1990s. For example, in 1993 there were 29 incidents ranking above level 1 on the International Nuclear Event Scale , and this number dropped under four per year in 1995–2003. The number of employees receiving annual radiation doses above 20 mSv , which is equivalent to a single full-body CT scan , saw a strong decline around 2000. In November 2015,

8514-515: The successful development of a new absorbent material dubbed HiCap which performs surface retention of solid or gas molecules, atoms or ions and also effectively removes toxic metals from water, according to results verified by researchers at Pacific Northwest National Laboratory . In 2005, ten countries accounted for the majority of the world's concentrated uranium oxides: Canada (27.9%), Australia (22.8%), Kazakhstan (10.5%), Russia (8.0%), Namibia (7.5%), Niger (7.4%), Uzbekistan (5.5%),

8613-513: The time splits into two smaller nuclei , releasing nuclear binding energy and more neutrons. If too many of these neutrons are absorbed by other uranium-235 nuclei, a nuclear chain reaction occurs that results in a burst of heat or (in some circumstances) an explosion. In a nuclear reactor, such a chain reaction is slowed and controlled by a neutron poison , absorbing some of the free neutrons. Such neutron absorbent materials are often part of reactor control rods (see nuclear reactor physics for

8712-448: The total population to around 41% of the population. Dominant languages now are Tswana, Sesotho, English, and Afrikaans, with many other languages being spoken, both local and international. English serves as the lingua franca for the town. Most local religions are catered for in Randfontein with the following being represented: Randfontein owes its existence to gold . JCI was greatly involved with mining ventures around Randfontein. In

8811-716: The use of such munitions by the US, UK and other countries during wars in the Persian Gulf and the Balkans raised questions concerning uranium compounds left in the soil (see Gulf War syndrome ). Depleted uranium is also used as a shielding material in some containers used to store and transport radioactive materials. While the metal itself is radioactive, its high density makes it more effective than lead in halting radiation from strong sources such as radium . Other uses of depleted uranium include counterweights for aircraft control surfaces, as ballast for missile re-entry vehicles and as

8910-528: The use of uranium in manufacturing and metalwork. Tools made with these formulas remained in use for several decades, until the Manhattan Project and the Cold War placed a large demand on uranium for fission research and weapon development. A team led by Enrico Fermi in 1934 found that bombarding uranium with neutrons produces beta rays ( electrons or positrons from the elements produced; see beta particle ). The fission products were at first mistaken for new elements with atomic numbers 93 and 94, which

9009-642: The west of the Randfontein Golf Course. The Show was cancelled for the first time in 2021 due to COVID-19 restrictions. In 2022 the Show was also cancelled due to COVID-19, and as of 2023 there is no longer a Randfontein Show. Slightly further afield are: A number of government departments have their regional offices in Randfontein. This includes SARS (Stubbs Street), SASSA (Stubbs Street), Department of Labour (Main Reef Road), and Department of Home Affairs (Main Reef Road). Being smaller offices than those in

9108-537: The whole facility (later, the town of Arco became the first in the world to have all its electricity come from nuclear power generated by BORAX-III , another reactor designed and operated by Argonne National Laboratory ). The world's first commercial scale nuclear power station, Obninsk in the Soviet Union , began generation with its reactor AM-1 on 27 June 1954. Other early nuclear power plants were Calder Hall in England, which began generation on 17 October 1956, and

9207-650: The world's largest single uranium deposit is located at the Olympic Dam Mine in South Australia . There is a significant reserve of uranium in Bakouma , a sub-prefecture in the prefecture of Mbomou in the Central African Republic . Some uranium also originates from dismantled nuclear weapons. For example, in 1993–2013 Russia supplied the United States with 15,000 tonnes of low-enriched uranium within

9306-628: The years, many have searched here for the Kruger Millions, but either nothing has been found, or the finder has kept very quiet about it. Central Suburbs : Outlying and Surroundings : From what can be established these are some of the oldest buildings in Randfontein: Robinson Lake is situated between the Randfontein Golf Course and the suburb of Robin Park. The lake was a former recreational lake filled from water that has been pumped from

9405-577: Was believed that uranium was relatively rare, and that nuclear proliferation could be avoided by simply buying up all known uranium stocks, but within a decade large deposits of it were discovered in many places around the world. The X-10 Graphite Reactor at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, formerly known as the Clinton Pile and X-10 Pile, was the world's second artificial nuclear reactor (after Enrico Fermi's Chicago Pile) and

9504-543: Was from ex-Soviet sources. From 1993 to 2005 the Material Protection, Control, and Accounting Program , operated by the federal government of the United States , spent about US$ 550 million to help safeguard uranium and plutonium stockpiles in Russia. This money was used for improvements and security enhancements at research and storage facilities. Safety of nuclear facilities in Russia has been significantly improved since

9603-599: Was promoted to the senior team. He joined Kaizer XI in 1969. He was one of the first Kaizer Chiefs recruits, he was recruited by Ewert Nene . He could play all positions on the field and he was a regular penalty taker. He was nicknamed "Banks" after 1966 World Cup winner and former Hellenic goalkeeper Gordon Banks , when he saved a fierce penalty kick from the British XI's Rod Marsh . He represented South Africa in 1977 versus Rhodesia . Randfontein Randfontein

9702-481: Was the first reactor designed and built for continuous operation. Argonne National Laboratory 's Experimental Breeder Reactor I , located at the Atomic Energy Commission's National Reactor Testing Station near Arco, Idaho , became the first nuclear reactor to create electricity on 20 December 1951. Initially, four 150-watt light bulbs were lit by the reactor, but improvements eventually enabled it to power

9801-450: Was working in his experimental laboratory in Berlin in 1789, Klaproth was able to precipitate a yellow compound (likely sodium diuranate ) by dissolving pitchblende in nitric acid and neutralizing the solution with sodium hydroxide . Klaproth assumed the yellow substance was the oxide of a yet-undiscovered element and heated it with charcoal to obtain a black powder, which he thought was

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