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29-522: The Armstrong Nugget is a gold nugget that was found June 19, 1913, by George Armstrong, at a placer mine near Susanville in Grant County , Oregon , United States . The nugget weighs 80.4 ounces. Today the nugget can be seen in a gold mining display at the U.S. Bank in Baker City . This geology article is a stub . You can help Misplaced Pages by expanding it . This Oregon -related article

58-504: Is a stub . You can help Misplaced Pages by expanding it . Gold nugget Nuggets are gold fragments weathered out of an original lode . They often show signs of abrasive polishing by stream action, and sometimes still contain inclusions of quartz or other lode matrix material. A 2007 study on Australian nuggets ruled out speculative theories of supergene formation via in-situ precipitation, cold welding of smaller particles, or bacterial concentration, since crystal structures of all of

87-510: Is considered to be sufficiently approximated by 31.10 g in EU directive 80/181/EEC. The Dutch troy system is based on a mark of 8 ounces, the ounce of 20 engels (pennyweights), the engel of 32 as. The mark was rated as 3,798 troy grains or 246.084 grammes. The divisions are identical to the tower system. The pennyweight symbol is dwt . One pennyweight weighs 24 grains, and 20 pennyweights make one troy ounce. Because there were 12 troy ounces in

116-793: Is displayed at the Banco Central Museum in Brazil along with the second and third largest nuggets remaining in existence, weighing respectively 1,506.2 troy ounces (46.85 kg; 103.28 lb) and 1,393.3 troy ounces (43.34 kg; 95.54 lb), which were also found at the Serra Pelada region. The largest gold nugget found using a metal detector is the Hand of Faith , weighing 875 troy ounces (27.2 kg; 60.0 lb), found in Kingower , Victoria, Australia in 1980. Historic large specimens include

145-469: Is equal to the grain unit of the avoirdupois system, but the troy ounce is heavier than the avoirdupois ounce, and the troy pound is lighter than the avoirdupois pound. Legally, one troy ounce (oz t) equals exactly 31.1034768 grams. Troy weight is generally supposed to take its name from the French market town of Troyes where English merchants traded at least as early as the early 9th century. The name troy

174-545: Is first attested in 1390, describing the weight of a platter, in an account of the travels in Europe of the Earl of Derby . Charles Moore Watson (1844–1916) proposes an alternative etymology: The Assize of Weights and Measures (also known as Tractatus de Ponderibus et Mensuris ), one of the statutes of uncertain date from the reign of either Henry III or Edward I , thus before 1307, specifies " troni ponderacionem "—which

203-733: Is sometimes confused with the similarly named Welcome Nugget , which was found in June 1858 at Bakery Hill, Ballarat, Australia by the Red Hill Mining Company. The Welcome weighed 2,218 troy ounces (69.0 kg; 152.1 lb). It was melted down in London in November 1859. The Canaã nugget, also known as the Pepita Canaa , was found on September 13, 1983, by miners at the Serra Pelada Mine in

232-531: The People's Bank of China has previously used troy measurements in minting Gold Pandas beginning in 1982; since 2016, the use of troy ounces has been replaced by integer numbers of grams. The troy pound (lb t) consists of twelve troy ounces and thus is 5 760 grains ( 373.241 72 grams). (An avoirdupois pound is approximately 21.53% heavier at 7 000 grains ( 453.592 37 grams), and consists of sixteen avoirdupois ounces). A troy ounce weighs 480 grains . Since

261-792: The crystalline " Fricot Nugget ", weighing 201 troy ounces (6.3 kg; 13.8 lb) – the largest one found during the California Gold Rush . It is on display at the California State Mining and Mineral Museum . The largest gold nugget ever found in California weighed 1,593 troy ounces (49.5 kg; 109.2 lb). It was found in August 1869 in Sierra Buttes by five partners – W.A. Farish, A. Wood, J. Winstead, F.N.L. Clevering and Harry Warner. The Victoria, Australia gold rush of

290-511: The 12-ounce troy pound in the 19th century. It has been retained, though rarely used, in the American system. Larger amounts of precious metals are conventionally counted in hundreds or thousands of troy ounces, or in kilograms. Troy ounces have been and are still often used in precious metal markets in countries that otherwise use International System of Units (SI), except in East Asia . However,

319-565: The Heron, was found in 1855 in Golden Gully in the Mount Alexander goldfield. It weighed 1,008 troy ounces (31.4 kg; 69.1 lb) and was found by a group of inexperienced miners who had received a supposedly empty claim. The miners found the nugget on their second day of digging; the nugget was named after one of the gold commissioners, a Mr. Heron. On 16 January 2013, a large gold nugget

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348-487: The Public Record Commissioners translate as "troy weight". The word troni refers to markets. Wright's The English Dialect Dictionary lists the word troi as meaning a balance , related to the alternate form 'tron' which also means market or the place of weighing. From this, Watson suggests that 'troy' derives from the manner of weighing by balance precious goods such as bullion or drugs; in contrast to

377-557: The State of Para, Brazil. Weighing 1,955 troy ounces (60.8 kg; 134.1 lb) gross, and containing 1,682.5 troy ounces (52.33 kg; 115.37 lb) of gold, it is among the largest gold nuggets ever found, and is, today, the largest in existence. The main controversy regarding this nugget is that the excavation reports suggest that the existing nugget was originally part of a nugget weighing 5,291.09 troy ounces (165 kg; 363 lb) that broke during excavations. The Canaã nugget

406-467: The adoption of the metric system, many systems of troy weights were in use in various parts of Europe, among them Holland troy, Paris troy, etc. Their values varied from one another by up to several percentage points. Troy weights were first used in England in the 15th century and were made official for gold and silver in 1527. The British Imperial system of weights and measures (also known as Imperial units )

435-707: The characteristics of the primary ore. Two gold nuggets are claimed as the largest in the world: the Welcome Stranger and the Canaã nugget, the latter being the largest surviving natural nugget. Considered by most authorities to be the biggest gold nugget ever found, the Welcome Stranger was found at Moliagul , Victoria, Australia in 1869 by John Deason and Richard Oates. It weighed gross, over 2,520 troy ounces (78 kg; 173 lb) and returned over 2,284 troy ounces (71.0 kg; 156.6 lb) net. The Welcome Stranger

464-480: The common rumour that Victoria 's goldfields were exhausted in the 19th century. Troy ounce Troy weight is a system of units of mass that originated in the Kingdom of England in the 15th century and is primarily used in the precious metals industry. The troy weight units are the grain , the pennyweight (24 grains), the troy ounce (20 pennyweights), and the troy pound (12 troy ounces). The troy grain

493-558: The continent. The troy ounce and grain were also part of the apothecaries' system . This was long used in medicine, but has been largely replaced by the metric system (milligrams). The only troy weight in widespread use is the British Imperial troy ounce and its American counterpart. Both are based on a grain of 0.06479891 gram (exact, by definition), with 480 grains to a troy ounce (compared with 437 + 1 ⁄ 2 grains for an ounce avoirdupois). The British Empire abolished

522-583: The early 1850s produced a number of large nuggets. They include the Welcome Nugget which weighed 68.98 kilograms (152.1 lb) which is considered to be the second largest gold nugget ever found. Another find, the Lady Hotham, which weighed 98.5 pounds (44.7 kg), was found by a group of nine miners on September 8, 1854, in Canadian Gully, Ballarat at a depth of 135 feet (41.2 m). The Lady Hotham

551-506: The form of British pre-decimal pennies, in which pounds, shillings, and pence were indicated using the symbols £ , s , and d , respectively. There is no specific 'troy grain'. All Imperial systems use the same measure of mass called a grain (historically of barley ), each weighing 1 ⁄ 7000 of an avoirdupois pound (and thus a little under 65 milligrams). Mint masses, also known as moneyers' masses , were legalized by Act of Parliament dated 17 July 1649 entitled An Act touching

580-475: The implementation of the international yard and pound agreement of 1 July 1959, the grain measure is defined as precisely 64.798 91   milligrams . Thus one troy ounce = 480 grains × 0.064 798 91 grams/grain = 31.103 476 80 grams. Since the ounce avoirdupois is defined as 437.5 grains, a troy ounce is exactly 480 ⁄ 437.5 = 192 ⁄ 175 or about 1.09714 ounces avoirdupois or about 9.7% more. The troy ounce for trading precious metals

609-460: The lower end of the spectrum. Purity can be roughly assessed by the nugget color, the richer and deeper the orange-yellow the higher the gold content. Nuggets are also referred to by their fineness , for example "865 fine" means the nugget is 865 parts per thousand in gold by mass. The common impurities are silver and copper . Nuggets high in silver content constitute the alloy electrum . The chemical composition of supergene gold nuggets can reveal

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638-618: The nuggets examined proved they were originally formed at high temperature deep underground (i.e., they were of hypogene origin). Other precious metals such as platinum form nuggets in the same way. A later study of native gold from Arizona , US, based on lead isotopes indicates that a significant part of the mass in alluvial gold nuggets in this area formed within the placer environment. Nuggets are usually 20K to 22K purity (83% to 92% by mass ). Gold nuggets in Australia often are 23K or slightly higher, while Alaskan nuggets are usually at

667-485: The old troy pound, there would have been 240 pennyweights to the pound (mass) – just as there were 240 pennies in the original pound-sterling . However, prior to 1526, the English pound sterling was based on the tower pound , which is 15 ⁄ 16 of a troy pound. The d in dwt stands for denarius , the ancient Roman coin that equates loosely to a penny. The symbol d for penny can be recognized in

696-492: The troy weight system of Bremen . (The Bremen troy ounce had a mass of 480.8 British Imperial grains.) Many aspects of the troy weight system were indirectly derived from the Roman monetary system . Before they used coins, early Romans used bronze bars of varying weights as currency. An aes grave ("heavy bronze") weighed one pound . One twelfth of an aes grave was called an uncia , or in English, an "ounce". Before

725-558: The word 'avoirdupois' used to describe bulk goods such as corn or coal, sometimes weighed in ancient times by a kind of steelyard called the auncel . Troy weight referred to the Tower system ; the earliest reference to the modern troy weights is in 1414. The origin of the troy weight system is unknown. Although the name probably comes from the Champagne fairs at Troyes , in northeastern France. English troy weights were nearly identical to

754-529: Was based on, and virtually identical with, the pre-1824 British troy ounce and the pre-1707 English troy ounce. (1824 was the year the British Imperial system of weights and measures was adopted; 1707 was the year of the Act of Union which created the Kingdom of Great Britain .) Troy ounces have been used in England since the early 15th century, and the English troy ounce was officially adopted for coinage in 1527. Before that time, various sorts of troy ounces were in use on

783-405: Was established in 1824, prior to which the troy weight system was a subset of pre-Imperial English units . The troy ounce in modern use is essentially the same as the British Imperial troy ounce (1824–1971), adopted as an official weight standard for United States coinage by act of Congress on May 19, 1828. The British Imperial troy ounce (known more commonly simply as the imperial troy ounce)

812-460: Was found near the city of Ballarat in Victoria, Australia by an amateur gold prospector. The Y-shaped nugget weighed slightly more than 5 kilograms (11 lb), measured around 22 cm high by 15 cm wide, and has a market value slightly below 300,000 Australian dollars , though opinions have been expressed that it could be sold for much more due to its rarity. The discovery has cast doubt on

841-518: Was named after the wife of the Governor, Sir Charles Hotham who happened to be visiting the area when the nugget was found. Eighteen months earlier, in January and early February 1853, three other large nuggets weighing 134 pounds (61 kg), 93.125 pounds (42.241 kg), and 83.5 pounds (37.9 kg) were also found in Canadian Gully at a depth of 55 to 60 feet (17 to 18 m). Another nugget,

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