San Francisco Mint
The San Francisco Mint is a branch of the United States Mint and was opened in 1854 to serve the gold mines of the California Gold Rush. It outgrew its first building and moved into a new one in 1874; this building, the Old United States Mint known affectionately as The Granite Lady, is one of the few that survived the great 1906 San Francisco earthquake. It served until 1937. Within the first year of its operation, the San Francisco mint turned $4 million in gold bullion into coins; the second building, completed in 1874, was designed by Alfred B. Mullett in a conservative Greek Revival style with a sober Doric order; the building had a central pedimented portico flanked by projecting wings in an E-shape. The building sat on a concrete and granite foundation, designed to thwart tunneling into its vaults, which at the time of the 1906 fire held $300 million a third of the United States' gold reserves. Heroic efforts by Superintendent of the Mint, Frank A. Leach, his men preserved the building and the bullion that backed the nation's currency.
The mint resumed operation soon thereafter, continuing until 1937. In 1961 the Old Mint, as it had become known, was designated a National Historic Landmark, it became a California Historical Landmark in 1974. The given name of "The Granite Lady" is somewhat of a misnomer as most of the building is made from sandstone. While the base/basement of the building is made of granite, the entire external and upper stories are made of sandstone; the Granite Lady was a marketing term given in the 1970s. The Old Mint was open to visitors until 1993. In 2003 the federal government sold the structure to the City of San Francisco for one dollar—an 1879 silver dollar struck at the mint— for use as a historical museum to be called the San Francisco Museum at the Mint. In the fall of 2005, ground was broken for renovations that would turn the central court into a glass-enclosed galleria. In 2006 Congress created the San Francisco Old Mint Commemorative Coin, the first coin to honor a United States mint; the first phase of renovations were completed in 2011.
In 2014, the San Francisco Museum and Historical Society began raising money for the second phase, which would have included permanent exhibitions. In 2015, the City of San Francisco looked for a new tenant to renovate and program the space with Activate San Francisco Events being selected as an interim tenant; as the City's 2016 public re-opening event, continuing the tradition of a similar event from past years, on the first weekend in March, the Old Mint hosted a "San Francisco History Days" event with over sixty participating historic organizations. Until a new tenant is found, the Old Mint will continue to be used for special events, some open to the public. In April 2016, the California Historical Society agreed to undertake the restoration of the building and its preservation as a public space; the new Mint was opened in 1937. Beginning in 1955, circulating coinage from San Francisco was suspended for 13 years. In 1968, it took over most proof coinage production from the Philadelphia Mint, but continued striking a supplemental circulating coinage from 1968 through 1974.
From 1975 to 2012, the San Francisco Mint has been used only for proof coinage, with the exception of the Susan B. Anthony dollar from 1979–81 and a portion of the mintage of cents in the early 1980s; the dollars bear a mintmark of an "S", but the cents are otherwise indistinguishable from those minted at Philadelphia. In 2012, the San Francisco mint started to mint circulation strike quarters in the America the Beautiful quarter series, marked with an "S" mintmark and only issued for collectors. From 1962 to 1988, the San Francisco Mint was an assay office; the San Francisco Mint only admits visitors on rare exception. On May 15, 1987, to commemorate the 50th anniversary of the Mint, a limited number of people were allowed to tour the facility; this tour was advertised in the San Francisco Chronicle newspaper, with a phone number to call to reserve a spot. In 2006, the United States Mint released a gold five dollar commemorative coin which commemorates the 100th year after the old San Francisco mint survived an earthquake.
The mint played a part in the city's recovery after the earthquake, providing shelter for many as it was one of the few buildings left standing. The coin was minted as both a proof coin and an uncirculated coin, is no longer available directly from the United States Mint. On June 15, 2006 President George W. Bush signed Public Law 109-230, legislation authorizing the production of the 2006 San Francisco $5 commemorative gold coin as well as its $1 silver counterpart; the production of the $5 denomination was limited to a maximum mintage of 100,000 coins, but separate mintage figures for each of the proof and uncirculated coins have not yet been released. The $1 silver version was limited to only 500,000 coins, both in proof and uncirculated products, but distinct mintage figures for both products has not been stated; the obverse was sculpted by Joseph Menna. Features Coin Finishes: proof, uncirculated Maximum Mintage: 100,000 - The final mintages were 16,938 uncirculated, 47,275 proof. United States Mint Facility: San Francisco Public Law: 109-230 In 2006, t
Dolphin is a common name of aquatic mammals within the order Cetacea, arbitrarily excluding whales and porpoises. The term dolphin refers to the extant families Delphinidae, Platanistidae and Pontoporiidae, the extinct Lipotidae. There are 40 extant species named as dolphins. Dolphins range in size from the 1.7 m long and 50 kg Maui's dolphin to the 9.5 m and 10 t killer whale. Several species exhibit sexual dimorphism, they have two limbs that are modified into flippers. Though not quite as flexible as seals, some dolphins can travel at 55.5 km/h. Dolphins use their conical shaped teeth to capture fast moving prey, they have well-developed hearing, adapted for both air and water and is so well developed that some can survive if they are blind. Some species are well adapted for diving to great depths, they have a layer of blubber, under the skin to keep warm in the cold water. Although dolphins are widespread, most species prefer the warmer waters of the tropic zones, but some, like the right whale dolphin, prefer colder climates.
Dolphins feed on fish and squid, but a few, like the killer whale, feed on large mammals, like seals. Male dolphins mate with multiple females every year, but females only mate every two to three years. Calves are born in the spring and summer months and females bear all the responsibility for raising them. Mothers of some species fast and nurse their young for a long period of time. Dolphins produce a variety of vocalizations in the form of clicks and whistles. Dolphins are sometimes hunted in places such as Japan, in an activity known as dolphin drive hunting. Besides drive hunting, they face threats from bycatch, habitat loss, marine pollution. Dolphins have been depicted in various cultures worldwide. Dolphins feature in literature and film, as in the film series Free Willy. Dolphins are sometimes trained to perform tricks; the most common dolphin species in captivity is the bottlenose dolphin, while there are around 60 captive killer whales. The name is from Greek δελφίς, "dolphin", related to the Greek δελφύς, "womb".
The animal's name can therefore be interpreted as meaning "a'fish' with a womb". The name was transmitted via the Latin delphinus, which in Medieval Latin became dolfinus and in Old French daulphin, which reintroduced the ph into the word; the term mereswine has historically been used. The term'dolphin' can be used to refer to, under the parvorder Odontoceti, all the species in the family Delphinidae and the river dolphin families Iniidae, Pontoporiidae and Platanistidae; this term has been misused in the US in the fishing industry, where all small cetaceans are considered porpoises, while the fish dorado is called dolphin fish. In common usage the term'whale' is used only for the larger cetacean species, while the smaller ones with a beaked or longer nose are considered'dolphins'; the name'dolphin' is used casually as a synonym for bottlenose dolphin, the most common and familiar species of dolphin. There are six species of dolphins thought of as whales, collectively known as blackfish: the killer whale, the melon-headed whale, the pygmy killer whale, the false killer whale, the two species of pilot whales, all of which are classified under the family Delphinidae and qualify as dolphins.
Though the terms'dolphin' and'porpoise' are sometimes used interchangeably, porpoises are not considered dolphins and have different physical features such as a shorter beak and spade-shaped teeth. Porpoises share a common ancestry with the Delphinidae. A group of dolphins is called a "school" or a "pod". Male dolphins are called "bulls", females "cows" and young dolphins are called "calves". Parvorder Odontoceti, toothed whales Family Platanistidae Ganges and Indus river dolphin, Platanista gangetica with two subspecies Ganges river dolphin, Platanista gangetica gangetica Indus river dolphin, Platanista gangetica minor Family Iniidae Amazon river dolphin, Inia geoffrensis Orinoco river dolphin, Inia geoffrensis humboldtiana Araguaian river dolphin, Inia Araguaiaensis Bolivian river dolphin, Inia boliviensis Family Lipotidae Baiji, Lipotes vexillifer Family Pontoporiidae La Plata dolphin, Pontoporia blainvillei Family Delphinidae, oceanic dolphins Genus Delphinus Long-beaked common dolphin, Delphinus capensis Short-beaked common dolphin, Delphinus delphis Genus Tursiops Common bottlenose dolphin, Tursiops truncatus Indo-Pacific bottlenose dolphin, Tursiops aduncus Burrunan dolphin, Tursiops australis, a newly discovered species from the sea around Melbourne in September 2011.
Genus Lissodelphis Northern right whale dolphin, Lissodelphis borealis Southern right whale dolphin, Lissodelphis peronii Genus Sotalia Tucuxi, Sotalia fluviatilis Costero, Sotalia guianensis Genus Sousa Indo-Pacific humpback dolphin, Sousa chinensis Chinese white dolphin, Sousa chinensis chinensis Atlantic humpback dolphin, Sousa teuszii Genus Stenella Atlantic spotted dolphin, Stenella frontalis Clymene dolphin, Stenella clymene Pantropical
Panama–Pacific commemorative coins
The five Panama–Pacific commemorative coins were produced in connection with the 1915 Panama–Pacific International Exposition in San Francisco. Struck at that city's mint, the issue included octagonal $50 pieces. Excepting modern bullion coins, these two gold pieces are the highest denomination issued and the largest coins struck by the United States Mint; the octagonal $50 piece is the only U. S. coin to be issued, not round. In January 1915, Congress passed legislation for a silver half dollar, as well as a gold dollar, quarter eagle, two $50 pieces: one round and one octagonal; the Mint had consulted artists. Treasury Secretary William G. McAdoo rejected all their designs. Two of them, Robert I. Aitken for the $50 pieces and Charles Keck for the gold dollar and their submissions were used; the half dollar and quarter eagle were designed by Chief Engraver Charles E. Barber with the participation of his longtime assistant, George T. Morgan; the coins were vended at the Exposition by prominent numismatist Farran Zerbe.
They did not sell well, many of each denomination were returned for melting. Only a few hundred of each of the $50 pieces were distributed, making them the lowest-mintage commemorative coins, they catalog depending on condition. Private gold pieces, sometimes dubbed "pioneer gold", were struck several times during the 19th century from locally produced bullion in areas where federal coins were scarce; these unofficial coins came from sites ranging from Georgia to Oregon. Many, ranging in denomination from 25 cents to 50 dollars, are relics of the California Gold Rush and its aftermath; the fifty-dollar denomination was struck by private minters such as Co.. The private $50 pieces were round in form, but those struck by Augustus Humbert for the U. S. Assay Office at San Francisco, prior to the establishment of the San Francisco Mint in 1854, were octagonal. Humbert's pieces were not money in a legal sense, as Congress had not authorized them as legal tender, were deemed ingots, they contained their full value in gold.
Bearing the denomination "Fifty Dollars", they were called "slugs" or "quintuple eagles" by the public. They circulated in California and elsewhere in the Far West, were accepted on par with federal gold coins. All of these $50 pieces, public or private, are rare and valuable today: One of Humbert's octagonal pieces, dated 1851 and with a lettered edge, sold at auction in 2010 for $546,250; the only $50 piece produced by the United States Bureau of the Mint prior to 1915 was the 1877 pattern half union, produced experimentally at the Philadelphia Mint, though it was not approved as a circulating coin. In 1904, San Francisco merchant Rueben Hale proposed an exposition in his home city for 1915, both to commemorate the opening of the Panama Canal and to mark the 400th anniversary of Vasco Núñez de Balboa becoming the first European known to view the Pacific Ocean from the Americas: in phrasing current, he discovered the Pacific. Although the 1906 San Francisco earthquake and fire caused a momentary setback to these plans, it sparked additional fundraising.
Many of the wealthiest in California gave financial support, the state matched private donations dollar for dollar, in 1911, President William Howard Taft selected San Francisco over its competitor, New Orleans, to host the fair. The Panama–Pacific International Exposition, constructed in San Francisco by the Golden Gate at a cost of $50 million, was open from February 20, 1915, to December 4, 1915. About 19,000,000 people attended, the exposition was a great success, generating enough profit to build the San Francisco Civic Auditorium with about $1 million remaining; the Palace of Fine Arts is the only building from the fair. Commemorative coins were not sold to the public by the Mint, as they subsequently have been. Instead, a commemorative's authorizing legislation would designate a group or organization to purchase the coins from the Mint at face value, sell them to the public as a fundraiser. Among those who had pushed for commemorative legislation in the past, had been involved in the sale of the resulting coins, was Farran Zerbe, a collector and numismatic promoter who had by 1914 served as president of the American Numismatic Association.
Zerbe was a controversial figure—some felt the coins with which he had been involved had been sold at inflated prices—but he helped promote the hobby with his exhibit, "Money of the World", which became part of the Chase Manhattan Money Museum. Several proposals for commemorative coins had been introduced by mid-1914, though none had been issued by the Mint since 1905. One, sponsored by New York Senator Elihu Root, called for a commemorative quarter dollar marking a century of peace, as well as the August 1914 opening of the Panama Canal. Two bills were introduced calling for coins to commemorate and benefit the Panama–Pacific Exposition. R. 16902 was introduced by California Congressman Julius Kahn on June 3, 1914. Senate bill 6309 was introduced in that body by New Jersey Senator James E. Martine on July 6; this bill called for two $50 pieces, a quarter eagle or $2.50 in gold, a commemorative gold dollar, a half dollar. The octagonal pieces were intended to recall the unofficial $50 coins struck during the Gold RushMartine's bill passed the Senate on August 3, having been approved by the Committee on Industrial Expositions, to which it had been referred.
The only objection was procedural, by Utah's Reed Smoot: that the bill should have instead been referred to and approved by the Senate Committee on Banking and Currency, or its Committee on Finance. Neither Smoot nor any other senator obje
The gold dollar or gold one-dollar piece is a gold coin, struck as a regular issue by the United States Bureau of the Mint from 1849 to 1889. The coin had three types over its lifetime, all designed by Mint Chief Engraver James B. Longacre; the Type 1 issue has the smallest diameter of any United States coin minted to date. A gold dollar coin had been proposed several times in the 1830s and 1840s, but was not adopted. Congress was galvanized into action by the increased supply of bullion caused by the California gold rush, in 1849 authorized a gold dollar. In its early years, silver coins were being hoarded or exported, the gold dollar found a ready place in commerce. Silver again circulated after Congress in 1853 required that new coins of that metal be made lighter, the gold dollar became a rarity in commerce before federal coins vanished from circulation because of the economic disruption caused by the American Civil War. Gold did not again circulate in most of the nation until 1879. In its final years, it was struck in small numbers.
It was in demand to be mounted in jewelry. The regular issue gold dollar was last struck in 1889. Damaged common date gold dollars tend to be worth anywhere from melt value to about US$110. In proposing his plan for a mint and a coinage system, Secretary of the Treasury Alexander Hamilton in 1791 proposed that the one-dollar denomination be struck both as a gold coin, as one of silver, representative of the two metals which he proposed be made legal tender. Congress followed Hamilton's recommendation only in part, authorizing a silver dollar, but no coin of that denomination in gold. In 1831, the first gold dollar was minted, at the private mint of Christopher Bechtler in North Carolina. Much of the gold being produced in the United States came from the mountains of North Carolina and Georgia, the dollars and other small gold coins issued by Bechtler circulated through that region, were now and seen further away. Additional one-dollar pieces were struck by Christopher's son. Soon after the Bechtlers began to strike their private issues, Secretary of the Treasury Levi Woodbury became an advocate of having the Mint of the United States strike the one-dollar denomination in gold.
He was opposed by Robert M. Patterson. Woodbury persuaded President Andrew Jackson to have pattern coins struck. In response, Patterson had Mint Second Engraver Christian Gobrecht break off work on the new design for the silver one-dollar coin and work on a pattern for the gold dollar. Gobrecht's design featured a Liberty cap surrounded by rays on one side, a palm branch arranged in a circle with the denomination and name of the country on the other. Consideration was given to including the gold dollar as an authorized denomination in the revisionary legislation that became the Mint Act of 1837; the Philadelphia newspaper Public Ledger, in December 1836, supported a gold dollar, stating that "the dollar is the smallest gold coin that would be convenient, as it would be eminently so, neither silver nor paper should be allowed to take its place." After Mint Director Patterson appeared before a congressional committee, the provision authorizing the gold dollar was deleted from the bill. In January 1844, North Carolina Representative James Iver McKay, the chairman of the Committee on Ways and Means, solicited the views of Director Patterson on the gold dollar.
Patterson had more of Gobrecht's pattern dollar struck to show to committee members, again advising against a coin that if issued would be only about a half inch in diameter. He told Treasury Secretary John C. Spencer that the only gold coins of that size in commerce, the Spanish and Colombian half-escudos, were unpopular and had not been struck for more than twenty years; this seemed to satisfy the committee as nothing more was done for the time, when a gold dollar was proposed again in 1846, McKay's committee recommended against it. Before 1848, record amounts of gold were flowing to American mints to be struck into coin, but the California Gold Rush vastly increased these quantities; this renewed calls for a gold dollar, as well as for a higher denomination than the eagle the largest gold coin. In January 1849, McKay introduced a bill for a gold dollar, referred to his committee. There was much discussion in the press about the proposed coin. McKay amended his legislation to provide for a double eagle and wrote to Patterson, who replied stating that the annular gold dollar would not work, neither would another proposal to have dollar piece consisting of a gold plug in a silver coin.
Gobrecht's successor as chief engraver, James B. Longacre, prepared patterns, including some with a square hole in the middle. McKay got his fellow Democrat, New Hampshire Senator Charles Atherton, to introduce the bill to authorize the gold dollar and the double eagle in the Senate on February 1, 1849—Atherton was chairman of the Senate Finance Committee. McKay introduced a version into the House on February 20; the dollar was attacked by congressmen from the Whig Party in the minority, on the grounds that it would be too small, would be counterfeited and in bad light might be mistakenly spent as a half dime, the coins being similar in size. McKay did not resp
United States Sesquicentennial coinage
The United States Sesquicentennial coin issue consisted of a commemorative half dollar and quarter eagle struck in 1926 at the Philadelphia Mint for the 150th anniversary of American independence. The obverse of the half dollar features portraits of the first president, George Washington, the president in 1926, Calvin Coolidge, making it the only American coin to depict a president in his lifetime. By the March 1925 Act of Congress, by which the National Sesquicentennial Exhibition Commission was chartered, Congress allowed it to purchase 1,000,000 specially designed half dollars and 200,000 quarter eagles, which could be sold to the public at a premium; the Commission had trouble agreeing on a design with Mint Chief Engraver John R. Sinnock, asked Philadelphia attorney, arts patron and numismatist John Frederick Lewis to submit sketches; these were adapted by Sinnock, without giving credit to Lewis, whose involvement would not be known for forty years. Both the quarter eagle, designed by Sinnock, the half dollar were struck in the maximum number authorized, but many were returned to the Mint for melting when they failed to sell.
The Liberty Bell reverse for the half dollar was reused by Sinnock, again without giving Lewis credit, on the Chief Engraver's Franklin half dollar, first minted in 1948. Legislation for a commemorative coin to mark the 150th anniversary of American independence was introduced on behalf of the United States National Sesquicentennial Exhibition Commission, charged with organizing what became known as the Sesquicentennial Exposition in Philadelphia. In the Act of March 3, 1925, Congress both chartered the Commission and allowed one million half dollars and 200,000 quarter eagles to be struck in commemoration of the Sesquicentennial of American Independence; these coins would be sold only at face value. Profits would go to financing the Exposition; the original version of the bill, introduced in the House of Representatives on February 16, 1925 by Pennsylvania Congressman George P. Darrow and in the Senate by that state's George W. Pepper, called for a $1.50 gold coin for the 150th anniversary, for commemorative half dollars, for a $1 bill honoring the Declaration of Independence.
A hearing was held before the House Committee on Industrial Arts and Expositions two days at which Congressman Darrow predicted that the $1.50 gold pieces would not be opposed by either the Treasury or the Committee on Coinage and Measures, but he was incorrect. The Commission hoped to have commemoratives depicting the enlargement of the country through acquisitions such as the Louisiana Purchase and the Annexation of Texas, but these were not included in the final version of the bill; the Commission continued to pursue congressional approval of the $1.50 piece and the other proposed commemoratives at least through August 1925. In May, H. P. Caemmerer, secretary of the Commission of Fine Arts, a body charged with making recommendations on the approval of coinage design, wrote to the Sesquicentennial Commission, asking what they proposed to do about the coins. Having received no reply, he wrote again in late August, this time to Milton Medary, a member of the Fine Arts Commission, asking what progress had been made.
Medary replied that the Sesquicentennial Commission was in touch with the new Chief Engraver at the Philadelphia Mint, John R. Sinnock, but that Sinnock had not yet submitted satisfactory designs. Dissatisfied with Sinnock's work, the Sesquicentennial Commission hired John Frederick Lewis to create designs. Lewis, who served as president of the Pennsylvania Academy of Fine Arts from 1906 until his death in 1932, was known as a numismatist, but not as an artist. On December 8, 1925, Sesquicentennial Commission director Asher C. Baker submitted Lewis's sketches, which appear much like the present half dollar, to Fine Arts Commission chairman Charles Moore. Baker referred to Lewis's "designs for the coins", which may mean that he submitted sketches for the quarter eagle as well, but if so, they are not extant and were not acted upon by the Fine Arts Commission; the half dollar designs were approved by the Fine Arts Commission, on condition the sketches were converted into models by a competent sculptor, Moore sent them on December 11 to Mint Director Robert J. Grant.
The resultant plaster models, made by Sinnock, were submitted to the Fine Arts Commission on March 13, 1926, were undoubtedly endorsed, but the approval letter is lost. Sinnock's sketches for the quarter eagle were sent to the Fine Arts Commission on February 27, 1926, were forwarded to sculptor member Lorado Taft for his views. Moore sent his commission's approval to Grant on March 26, with several recommendations, including that the motto E Pluribus Unum, present on the obverse in Sinnock's sketches, the sun's rays on the reverse, be omitted; the rays were not removed, the motto was moved to the reverse. Approval of the models followed in April, again with minor suggestions; the obverse of the half dollar features jugate busts of George Washington, first president of the United States, Calvin Coolidge, the president in 1926. According to Anthony Swiatek and Walter Breen, "both were mistakes. Washington was not president of the Continental Congress in 1776, Coolidge's likeness was illegal. By an 1866 Act of Congress, no living person could be portrayed on U.
S. coins or currency. Although Sinnock had not designed a coin showing a president, he had created presidential medals under Chief Engraver
Gold is a chemical element with symbol Au and atomic number 79, making it one of the higher atomic number elements that occur naturally. In its purest form, it is a bright reddish yellow, soft and ductile metal. Chemically, gold is a group 11 element, it is solid under standard conditions. Gold occurs in free elemental form, as nuggets or grains, in rocks, in veins, in alluvial deposits, it occurs in a solid solution series with the native element silver and naturally alloyed with copper and palladium. Less it occurs in minerals as gold compounds with tellurium. Gold is resistant to most acids, though it does dissolve in aqua regia, a mixture of nitric acid and hydrochloric acid, which forms a soluble tetrachloroaurate anion. Gold is insoluble in nitric acid, which dissolves silver and base metals, a property that has long been used to refine gold and to confirm the presence of gold in metallic objects, giving rise to the term acid test. Gold dissolves in alkaline solutions of cyanide, which are used in mining and electroplating.
Gold dissolves in mercury, forming amalgam alloys. A rare element, gold is a precious metal, used for coinage and other arts throughout recorded history. In the past, a gold standard was implemented as a monetary policy, but gold coins ceased to be minted as a circulating currency in the 1930s, the world gold standard was abandoned for a fiat currency system after 1971. A total of 186,700 tonnes of gold exists above ground, as of 2015; the world consumption of new gold produced is about 50% in jewelry, 40% in investments, 10% in industry. Gold's high malleability, resistance to corrosion and most other chemical reactions, conductivity of electricity have led to its continued use in corrosion resistant electrical connectors in all types of computerized devices. Gold is used in infrared shielding, colored-glass production, gold leafing, tooth restoration. Certain gold salts are still used as anti-inflammatories in medicine; as of 2017, the world's largest gold producer by far was China with 440 tonnes per year.
Gold is the most malleable of all metals. It can be drawn into a monoatomic wire, stretched about twice before it breaks; such nanowires distort via formation and migration of dislocations and crystal twins without noticeable hardening. A single gram of gold can be beaten into a sheet of 1 square meter, an avoirdupois ounce into 300 square feet. Gold leaf can be beaten thin enough to become semi-transparent; the transmitted light appears greenish blue, because gold reflects yellow and red. Such semi-transparent sheets strongly reflect infrared light, making them useful as infrared shields in visors of heat-resistant suits, in sun-visors for spacesuits. Gold is a good conductor of electricity. Gold has a density of 19.3 g/cm3 identical to that of tungsten at 19.25 g/cm3. By comparison, the density of lead is 11.34 g/cm3, that of the densest element, osmium, is 22.588±0.015 g/cm3. Whereas most metals are gray or silvery white, gold is 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 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 important in commercial jewelry as these produce white gold alloys. Fourteen-karat gold-copper alloy is nearly identical in color to certain bronze alloys, both may be used to produce police and other badges. White gold alloys can be made with nickel. 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, purple gold can be made by alloying with aluminium. Less addition of manganese, aluminium and other elements can produce more unusual colors of gold for various applications. Colloidal gold, used by electron-microscopists, is red. Gold has only one stable isotope, 197Au, its only 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 195Au with a half-life of 186.1 days. The least stable is 171Au. Most of gold's radioisotopes with atomic masses below 197 decay by some combination of proton emission, α decay, β+ decay; the exceptions are 195Au, which decays by electron capture, 196Au, which decays most by electron capture with a minor β− decay path. All of gold's radioisotopes with atomic masses above 197 decay by β− decay. At least 32 nuclear isomers have been characterized, ranging in atomic mass from 170 to 200. Within that range, only 178Au, 180Au, 181Au, 182Au, 188Au do not have isomers. Gold's most stable isomer is 198m2Au with a half-life of 2.27 days. Gold's least stable isomer is 177m2Au with a half-life of only 7 ns. 184m1Au has three decay paths: β+ decay, isomeric
Pilgrim Tercentenary half dollar
The Pilgrim Tercentenary half dollar or Pilgrim half dollar was a commemorative fifty-cent coin struck by the United States Bureau of the Mint in 1920 and 1921 to mark the 300th anniversary of the arrival of the Pilgrims in North America. It was designed by Cyrus E. Dallin. Massachusetts Congressman Joseph Walsh was involved in joint federal and state efforts to mark the anniversary, he saw a reference to a proposed Maine Centennial half dollar and realized that a coin could be issued for the Pilgrim anniversary in support of the observances at Plymouth, Massachusetts. The bill moved through the legislative process and became the Act of May 12, 1920 with the signature of President Woodrow Wilson. Sculptor James Earle Fraser criticized some aspects of the design, but the Treasury approved it anyway. After a promising start, sales tailed off, tens of thousands of coins from each year were returned to the Philadelphia Mint for melting. Numismatist Q. David Bowers has cited the fact that the coins were struck in a second year as the start of a trend to force collectors to buy more than one piece in order to have a complete set.
The Pilgrims were Brownist English Dissenters. They differed from the Puritans, they had left England for the Netherlands because in 1608, King James I began to persecute Separatists. Among those who fled was William Bradford. Things became more difficult for the Separatists in the Netherlands in the late 1610s as the Dutch government moved towards alliance with England, they had few opportunities in the Netherlands as they were limited to manual labor by the guilds' refusal to accept them, they feared that their children were straying from their language and religion. Investors led by Thomas Weston agreed to finance an expedition to North America, the ship Speedwell was sent to fetch Separatists from the Netherlands join the larger Mayflower to form a two-ship expedition. After transporting the Separatists, the Speedwell proved unseaworthy for the ocean voyage; the Mayflower's passenger list was formed from some Separatists who had gone to the Netherlands and some who had stayed in England, as well as a scattering of others.
Some would-be pioneers had to be left behind because of the problems with the Speedwell. The Mayflower sailed from Plymouth, in South West England, on September 6, 1620, with 102 passengers and a crew of 47; the expedition sighted Cape Cod on November 9, 1620, landed at what is now Provincetown, Massachusetts. Two days the men signed the Mayflower Compact, wherein all agreed to submit themselves to the will of the majority—one of the foundation documents of American democracy, they established a settlement at Plymouth Colony, but they had expected to land further south and were ill-equipped for a Massachusetts winter. Half died. There had been few Native Americans in the area, but in 1621, the settlers were approached by a group, including two and Squanto, who spoke some English. Squanto taught the Pilgrims indigenous methods for cultivating corn, a plant native to the New World with which the emigrants were unfamiliar; this knowledge helped the Pilgrims become established. The Pilgrims grew in population slowly over the first generations in America, became a minority among settlers in the area.
In 1691, Plymouth Colony became part of the Province of Massachusetts Bay. Bradford's wife had died, he guided the colony from the communal economy necessary at first, to privatization increasing the harvest in the process. His diaries were published as Of Plymouth Plantation and constitute the major source of information concerning the Pilgrims' daily lives. In 1920, the government did not sell commemorative coins. Congress, during the early years of commemorative coinage designated a specific organization allowed to buy them at face value and to vend them to the public at a premium. In the case of the Pilgrim Tercentenary half dollar, the enabling legislation did not name an organization, but it was the Pilgrim Tercentenary Commission. Legislation for a Pilgrim Tercentenary half dollar was introduced in the House of Representatives by Massachusetts' Joseph Walsh on March 23, 1920, with the bill designated as H. R. 13227. It was referred to the Committee on Coinage and Measures, of which Indiana Congressman Albert Vestal was the chairman.
That committee held hearings on the bill on March 26, 1920, as well as on the coinage proposal that would become the Alabama Centennial half dollar, the first order of business. Once the committee voted to favorably recommend the Alabama bill, which provided for 100,000 half dollars, it proceeded to consider the Pilgrim proposal. Vestal had two days written to Treasury Secretary David F. Houston, Houston responded that while his department had not opposed the Maine Centennial or Alabama coinage bills, the Treasury had concerns that issuing large numbers of different designs would aid fraudsters. Walsh appeared and explained to the committee that Congress had authorized a commission to work with state and local authorities in planning for observances which were to be held in December 1920 on the 300th anniversary of the Mayflo