1.
Tombstone Courthouse State Historic Park
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Tombstone Courthouse State Historic Park is a state park of Arizona in the United States. Located in Tombstone, the park preserves the original Cochise County courthouse, the park was one of the first to be designated as a state park and in 1959 was the first to open following the 1957 establishment of the Arizona State Parks Board. The town of Tombstone was incorporated in 1879, by 1881 the town had grown to more than 7,000 population, stage robberies were no longer novel events. But more important than the lawlessness, Tombstone miners and merchants had to travel 150 dusty roundtrip miles to Tucson to record mining claims, deeds, contracts, etc. at the Pima County Courthouse. At the time, the area was part of Pima County with the county seat Tucson being a rugged two-day, Cochise county was formed in 1881 from the eastern part of Pima County, and Tombstone became its seat. A new courthouse was built the year and housed all of the county’s offices. The Sheriff of Cochise County had his office on the floor, first door to the right. Sheriff John Behan and his successors gradually instilled the idea that the arena for conflict was the courtroom upstairs rather than the street. Except for the Earp - Clanton feud, which gave Tombstone an extremely bad press from which it has no interest in recovering, the Tombstone courthouse represents a practical solution to the problem of securing lives and property in unorganized or poorly governed territory. It was put into effect quickly, without fumbling by men practiced in the process through their experience in Colorado, Utah, Nevada, Tombstone remained the county seat until 1929, when outvoted by a growing Bisbee, and the county seat was moved there. The last county office left the courthouse in 1931, except for an ill-fated attempt to convert the courthouse into a hotel during the 1940s, the building stood vacant until 1955. When the Tombstone Restoration Commission acquired it, they began the courthouse rehabilitation and it features exhibits and thousands of artifacts which tell of Tombstones colorful past. The courthouse in Tombstone is an elegant example of Territorial Victorian, the Tombstone courthouse is the oldest courthouse still standing in Arizona, At the time it was built it was one of the largest buildings in Arizona Territory. The building measures 76 feet in width, the shaft of the cruciform structure measures 40 feet wide. The first segment to be built is 88 feet long overall, the addition to the jail and courtroom brought the total to 116 feet in length. The building is a red brick structure built with five courses of runners. Exterior angles are quoined with white stone and/white stone dripstone course separates the lower and upper half of the building, a one story cupola or observation tower with a mansard roof wears a lacy gingerbread cresting that creates a kind of widows walk atop all. The double-hung eight-pane windows, are set in heavy frames topped by a bracketed, the eave-line is deeply recessed and strongly accented with simple dentils as are the pediments of the gable ends
2.
Arizona
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Arizona is a state in the southwestern region of the United States. It is also part of the Western United States and the Mountain West states and it is the sixth largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix, Arizona is one of the Four Corners states. It has borders with New Mexico, Utah, Nevada, California, and Mexico, Arizonas border with Mexico is 389 miles long, on the northern border of the Mexican states of Sonora and Baja California. Arizona is the 48th state and last of the states to be admitted to the Union. Historically part of the territory of Alta California in New Spain, after being defeated in the Mexican–American War, Mexico ceded much of this territory to the United States in 1848. The southernmost portion of the state was acquired in 1853 through the Gadsden Purchase, Southern Arizona is known for its desert climate, with very hot summers and mild winters. There are ski resorts in the areas of Flagstaff, Alpine, in addition to the Grand Canyon National Park, there are several national forests, national parks, and national monuments. To the European settlers, their pronunciation sounded like Arissona, the area is still known as alĭ ṣonak in the Oodham language. Another possible origin is the Basque phrase haritz ona, as there were numerous Basque sheepherders in the area, There is a misconception that the states name originated from the Spanish term Árida Zona. See also lists of counties, islands, rivers, lakes, state parks, national parks, Arizona is in the Southwestern United States as one of the Four Corners states. Arizona is the sixth largest state by area, ranked after New Mexico, of the states 113,998 square miles, approximately 15% is privately owned. The remaining area is public forest and park land, state trust land, Arizona is well known for its desert Basin and Range region in the states southern portions, which is rich in a landscape of xerophyte plants such as the cactus. This regions topography was shaped by volcanism, followed by the cooling-off. Its climate has hot summers and mild winters. The state is well known for its pine-covered north-central portion of the high country of the Colorado Plateau. Like other states of the Southwest United States, Arizona has an abundance of mountains, despite the states aridity, 27% of Arizona is forest, a percentage comparable to modern-day France or Germany. The worlds largest stand of pine trees is in Arizona
3.
Gold
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Gold is a chemical element with symbol Au and atomic number 79. In its purest form, it is a bright, slightly yellow, dense, soft, malleable. Chemically, gold is a metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions, Gold often occurs in free elemental form, as nuggets or grains, in rocks, in veins, and in alluvial deposits. It occurs in a solid solution series with the element silver and also naturally alloyed with copper. Less commonly, it occurs in minerals as gold compounds, often with tellurium, golds atomic number of 79 makes it one of the higher numbered, naturally occurring elements. It is thought to have produced in supernova nucleosynthesis, from the collision of neutron stars. Because the Earth was molten when it was formed, almost all of the present in the early Earth probably sank into the planetary core. Gold is resistant to most acids, though it does dissolve in aqua regia, a mixture of acid and hydrochloric acid. Gold also dissolves in solutions of cyanide, which are used in mining and electroplating. Gold dissolves in mercury, forming amalgam alloys, but this is not a chemical reaction, as a precious metal, gold has been used for coinage, jewelry, and other arts throughout recorded history. A total of 186,700 tonnes of gold is in existence above ground, the world consumption of new gold produced is about 50% in jewelry, 40% in investments, and 10% in industry. Gold is also used in infrared shielding, colored-glass production, gold leafing, certain gold salts are still used as anti-inflammatories in medicine. As of 2014, the worlds largest gold producer by far was China with 450 tonnes, Gold is cognate with similar words in many Germanic languages, deriving via Proto-Germanic *gulþą from Proto-Indo-European *ǵʰelh₃-. The symbol Au is from the Latin, aurum, the Latin word for gold, the Proto-Indo-European ancestor of aurum was *h₂é-h₂us-o-, meaning glow. This word is derived from the root as *h₂éu̯sōs, the ancestor of the Latin word Aurora. This etymological relationship is presumably behind the frequent claim in scientific publications that aurum meant shining dawn, Gold is the most malleable of all metals, a single gram can be beaten into a sheet of 1 square meter, and an avoirdupois ounce into 300 square feet. Gold leaf can be thin enough to become semi-transparent
4.
Metal
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A metal is a material that is typically hard, opaque, shiny, and has good electrical and thermal conductivity. Metals are generally malleable—that is, they can be hammered or pressed permanently out of shape without breaking or cracking—as well as fusible and ductile, about 91 of the 118 elements in the periodic table are metals, the others are nonmetals or metalloids. Some elements appear in both metallic and non-metallic forms, astrophysicists use the term metal to collectively describe all elements other than hydrogen and helium, the simplest two, in a star. The star fuses smaller atoms, mostly hydrogen and helium, to larger ones over its lifetime. In that sense, the metallicity of an object is the proportion of its matter made up of all chemical elements. Many elements and compounds that are not normally classified as metals become metallic under high pressures, the atoms of metallic substances are typically arranged in one of three common crystal structures, namely body-centered cubic, face-centered cubic, and hexagonal close-packed. In bcc, each atom is positioned at the center of a cube of eight others, in fcc and hcp, each atom is surrounded by twelve others, but the stacking of the layers differs. Some metals adopt different structures depending on the temperature, atoms of metals readily lose their outer shell electrons, resulting in a free flowing cloud of electrons within their otherwise solid arrangement. This provides the ability of metallic substances to easily transmit heat, while this flow of electrons occurs, the solid characteristic of the metal is produced by electrostatic interactions between each atom and the electron cloud. This type of bond is called a metallic bond, Metals are usually inclined to form cations through electron loss, reacting with oxygen in the air to form oxides over various timescales. Examples,4 Na + O2 →2 Na2O2 Ca + O2 →2 CaO4 Al +3 O2 →2 Al2O3, the transition metals are slower to oxidize because they form a passivating layer of oxide that protects the interior. Others, like palladium, platinum and gold, do not react with the atmosphere at all, some metals form a barrier layer of oxide on their surface which cannot be penetrated by further oxygen molecules and thus retain their shiny appearance and good conductivity for many decades. The oxides of metals are generally basic, as opposed to those of nonmetals, exceptions are largely oxides with very high oxidation states such as CrO3, Mn2O7, and OsO4, which have strictly acidic reactions. Painting, anodizing or plating metals are good ways to prevent their corrosion, however, a more reactive metal in the electrochemical series must be chosen for coating, especially when chipping of the coating is expected. Water and the two form an electrochemical cell, and if the coating is less reactive than the coatee. Metals in general have high conductivity, high thermal conductivity. Typically they are malleable and ductile, deforming under stress without cleaving, in terms of optical properties, metals are shiny and lustrous. Sheets of metal beyond a few micrometres in thickness appear opaque, although most metals have higher densities than most nonmetals, there is wide variation in their densities, lithium being the least dense solid element and osmium the densest
5.
Alloy
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An alloy is a mixture of metals or a mixture of a metal and another element. Alloys are defined by a metallic bonding character, an alloy may be a solid solution of metal elements or a mixture of metallic phases. Intermetallic compounds are alloys with a stoichiometry and crystal structure. Zintl phases are sometimes considered alloys depending on bond types. Alloys are used in a variety of applications. In some cases, a combination of metals may reduce the overall cost of the material while preserving important properties, in other cases, the combination of metals imparts synergistic properties to the constituent metal elements such as corrosion resistance or mechanical strength. Examples of alloys are steel, solder, brass, pewter, duralumin, bronze, the alloy constituents are usually measured by mass. Alloys are usually classified as substitutional or interstitial alloys, depending on the arrangement that forms the alloy. They can be classified as homogeneous, or heterogeneous or intermetallic. An alloy is a mixture of elements, which forms an impure substance that retains the characteristics of a metal. Alloys are made by mixing two or more elements, at least one of which is a metal and this is usually called the primary metal or the base metal, and the name of this metal may also be the name of the alloy. The other constituents may or may not be metals but, when mixed with the base, they will be soluble. The mechanical properties of alloys will often be different from those of its individual constituents. A metal that is very soft, such as aluminium, can be altered by alloying it with another soft metal. Although both metals are soft and ductile, the resulting aluminium alloy will have much greater strength. Adding a small amount of carbon to iron trades its great ductility for the greater strength of an alloy called steel. Due to its strength, but still substantial toughness, and its ability to be greatly altered by heat treatment, steel is one of the most useful. By adding chromium to steel, its resistance to corrosion can be enhanced, creating stainless steel, while adding silicon will alter its electrical characteristics, producing silicon steel
6.
Titration
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Titration, also known as titrimetry, is a common laboratory method of quantitative chemical analysis that is used to determine the unknown concentration of an identified analyte. Since volume measurements play a key role in titration, it is known as volumetric analysis. A reagent, called the titrant or titrator is prepared as a standard solution, a known concentration and volume of titrant reacts with a solution of analyte or titrand to determine concentration. The volume of titrant reacted is called titration volume, the word titration comes from the Latin word titulus, meaning inscription or title. The French word titre, also from this origin, means rank, volumetric analysis originated in late 18th-century France. François-Antoine-Henri Descroizilles developed the first burette in 1791, joseph Louis Gay-Lussac developed an improved version of the burette that included a side arm, and coined the terms pipette and burette in an 1824 paper on the standardization of indigo solutions. Depending on the endpoint desired, single drops or less than a drop of the titrant can make the difference between a permanent and temporary change in the indicator. Typical titrations require titrant and analyte to be in a liquid form, though solids are usually dissolved into an aqueous solution, other solvents such as glacial acetic acid or ethanol are used for special purposes. Concentrated analytes are diluted to improve accuracy. Many non-acid-base titrations require a constant pH throughout the reaction, therefore, a buffer solution may be added to the titration chamber to maintain the pH. Some redox reactions may require heating the solution and titrating while the solution is still hot to increase the reaction rate. For instance, the oxidation of some oxalate solutions requires heating to 60 °C to maintain a rate of reaction. In an acid-base titration, the titration curve reflects the strength of the corresponding acid, for a strong acid and a strong base, the curve will be relatively smooth and very steep near the equivalence point. Because of this, a change in titrant volume near the equivalence point results in a large pH change. If one reagent is an acid or base and the other is a strong acid or base, the titration curve is irregular. For example, the curve for the titration between oxalic acid and sodium hydroxide is pictured. The equivalence point occurs between pH 8-10, indicating the solution is basic at the point and an indicator such as phenolphthalein would be appropriate. Titrations between an acid and a weak base have titration curves which are highly irregular
7.
X-ray fluorescence
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X-ray fluorescence is the emission of characteristic secondary X-rays from a material that has been excited by bombarding with high-energy X-rays or gamma rays. When materials are exposed to short-wavelength X-rays or to gamma rays, ionization consists of the ejection of one or more electrons from the atom, and may occur if the atom is exposed to radiation with an energy greater than its ionization energy. X-rays and gamma rays can be enough to expel tightly held electrons from the inner orbitals of the atom. The removal of an electron in this way makes the structure of the atom unstable. In falling, energy is released in the form of a photon, thus, the material emits radiation, which has energy characteristic of the atoms present. The term fluorescence is applied to phenomena in which the absorption of radiation of a specific energy results in the re-emission of radiation of a different energy, each element has electronic orbitals of characteristic energy. Following removal of an electron by an energetic photon provided by a primary radiation source. There are a number of ways in which this can happen. The main transitions are given names, an L→K transition is traditionally called Kα, an M→K transition is called Kβ, an M→L transition is called Lα, and so on. Each of these transitions yields a fluorescent photon with an energy equal to the difference in energy of the initial and final orbital. Once sorted, the intensity of each characteristic radiation is directly related to the amount of element in the material. This is the basis of a technique in analytical chemistry. Figure 2 shows the form of the sharp fluorescent spectral lines obtained in the wavelength-dispersive method. In order to excite the atoms, a source of radiation is required, conventional X-ray generators are most commonly used, because their output can readily be tuned for the application, and because higher power can be deployed relative to other techniques. However, gamma ray sources can be used without the need for a power supply. When the energy source is a synchrotron or the X-rays are focused by an optic like a polycapillary, as a result, atomic information on the sub-micrometre scale can be obtained. X-ray generators in the range 20–60 kV are used, which allow excitation of a range of atoms. The continuous spectrum consists of bremsstrahlung radiation, radiation produced when high-energy electrons passing through the tube are progressively decelerated by the material of the tube anode, a typical tube output spectrum is shown in figure 3
8.
Radiolarite
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Radiolarite is a siliceous, comparatively hard, fine-grained, chert-like, and homogeneous sedimentary rock that is composed predominantly of the microscopic remains of radiolarians. This term is used for indurated radiolarian oozes and sometimes as a synonym of radiolarian earth. However, radiolarian earth is regarded by Earth scientists to be the unconsolidated equivalent of a radiolarite. A radiolarian chert is well-bedded, microcrystalline radiolarite that has a well-developed siliceous cement or groundmass, radiolarites are biogenic, marine, finely layered sedimentary rocks. The layers reveal an interchange of clastic mica grains, radiolarian tests, carbonates, clay minerals are usually not abundant. Radiolarites deposited in shallow depths can interleave with carbonate layers. Yet most often radiolarites are pelagic, deep water sediments, radiolarites are very brittle rocks and hard to split. They break conchoidally with sharp edges, during weathering they decompose into small, rectangular pieces. The colors range from light to dark via red, green, radiolarites are composed mainly of radiolarian tests and their fragments. The skeletal material consists of amorphous silica, radiolarians are marine, planktonic protists with an inner skeleton. Their sizes range from 0.1 to 0.5 millimeters, amongst their major orders albaillellaria, ectinaria, the spherical spumellaria and the hood-shaped nassellaria can be distinguished. According to Takahashi radiolarians stay for 2 to 6 weeks in the zone before they start sinking. Their descent through 5000 meters of water can take from two weeks to as long as 14 months. As soon as the protist dies and starts decaying silica dissolution affects the skeleton, the dissolution of silica in the oceans parallels the temperature/depth curve and is most effective in the uppermost 750 meters of the water column, farther below it rapidly diminishes. Upon reaching the interface the dissolution drastically increases again. Several centimeters below this interface the dissolution continues also within the sediment and it is in fact astonishing that any radiolarian tests survive at all. It is estimated that only as little as one percent of the skeletal material is preserved in radiolarian oozes. The organic wrappings act as a protection for the tests and spare them from dissolution, after deposition diagenetic processes start affecting the freshly laid down sediment
9.
Slate
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Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. It is the finest grained foliated metamorphic rock, foliation may not correspond to the original sedimentary layering, but instead is in planes perpendicular to the direction of metamorphic compression. The foliation in slate is called slaty cleavage and it is caused by strong compression causing fine grained clay flakes to regrow in planes perpendicular to the compression. Slate is frequently grey in color, especially when seen, en masse, Slate is not to be confused with shale, from which it may be formed, or schist. The word slate is used for certain types of object made from slate rock. It may mean a single roofing tile made of slate, or a writing slate and this was traditionally a small smooth piece of the rock, often framed in wood, used with chalk as a notepad or noticeboard, and especially for recording charges in pubs and inns. The phrases clean slate and blank slate come from this usage, before the mid-19th century, the terms slate, shale and schist were not sharply distinguished. In the context of underground mining in the United States. For example, roof slate referred to shale above a coal seam, occasionally, as in the purple slates of North Wales, ferrous reduction spheres form around iron nuclei, leaving a light green spotted texture. These spheres are sometimes deformed by a subsequent applied stress field to ovoids, Slate can be made into roofing slates, a type of roof shingle, or more specifically a type of roof tile, which are installed by a slater. Slate has two lines of breakability – cleavage and grain – which make it possible to split the stone into thin sheets, when broken, slate retains a natural appearance while remaining relatively flat and easy to stack. Slate is particularly suitable as a material as it has an extremely low water absorption index of less than 0. 4%. In fact, this natural slate, which requires only minimal processing, has the lowest embodied energy of all roofing materials, natural slate is used by building professionals as a result of its beauty and durability. Slate is incredibly durable and can last several hundred years, often little or no maintenance. Its low water makes it very resistant to frost damage and breakage due to freezing. Natural slate is also fire resistant and energy efficient, Slate roof tiles are usually fixed either with nails, or with hooks as is common with Spanish slate. In the UK, fixing is typically with double nails onto timber battens or nailed directly onto timber sarking boards, nails were traditionally of copper, although there are modern alloy and stainless steel alternatives. Both these methods, if used properly, provide a long-lasting weathertight roof with a lifespan of around 80–100 years, Slate roofs are still used today
10.
De re metallica
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De re metallica is a book cataloguing the state of the art of mining, refining, and smelting metals, published a year posthumously in 1556 due to a delay in preparing woodcuts for the text. The author was Georg Bauer, whose pen name was the Latinized Georgius Agricola, the book remained the authoritative text on mining for 180 years after its publication. It was also an important chemistry text for the period and is significant in the history of chemistry, mining was typically left to professionals, craftsmen and experts who were not eager to share their knowledge. Much experiential knowledge had been accumulated over the course of time and this knowledge was consecutively handed down orally within a small group of technicians and mining overseers. In the Middle Ages these people held the leading role as the master builders of the great cathedrals. It was a small, cosmopolitan elite within which existing knowledge was passed on and further developed, only a few writers from that time wrote anything about mining itself. Partly, that was because this knowledge was very difficult to access, most writers also found it simply not worth the effort to write about it. Only in the Renaissance did this begin to change. With the improved transport and the invention of the printing press knowledge spread much more easily, in 1500, the first printed book dedicated to mining engineering, called the “Nutzlich Bergbuchleyn” by Ulrich Rulein von Calw, was published. The most important works in this genre were, however, the twelve books De Re Metallica by Georgius Agricola, Agricola had spent nine years in the Bohemian town of Joachimsthal, now in the Czech Republic. After Joachimsthal, he spent the rest of his life in Chemnitz, both Joachimsthal and Chemnitz are in the Erzgebirge, or Ore Mountains. The book was influential, and for more than a century after it was published. The German mining technology it portrayed was acknowledged as the most advanced at the time, the book was reprinted in a number of Latin editions, as well as in German and Italian translations. Publication in Latin meant that it could be read by any educated European of the time, the numerous woodcuts and detailed descriptions of machinery made it a practical reference for those wishing to replicate the latest in mining technology. In 1912, the first English translation of De Re Metallica was privately published in London by subscription, the translators were Herbert Hoover, a mining engineer, and his wife, Lou Henry Hoover, a geologist and Latinist. The translation is not only for its clarity of language, but for the extensive footnotes. The most important translation—outside English—was the one published by the Deutsches Museum in Munich The book consists of a preface and twelve chapters, labelled books I to XII and it also has numerous woodcuts that provide annotated diagrams illustrating equipment and processes described in the text. Agricola addresses the book to prominent German aristocrats, the most important of whom were Maurice, Elector of Saxony and his brother Augustus and he then describes the works of ancient and contemporary writers on mining and metallurgy, the chief ancient source being Pliny the Elder
11.
New York (state)
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New York is a state in the northeastern United States, and is the 27th-most extensive, fourth-most populous, and seventh-most densely populated U. S. state. New York is bordered by New Jersey and Pennsylvania to the south and Connecticut, Massachusetts, and Vermont to the east. With an estimated population of 8.55 million in 2015, New York City is the most populous city in the United States, the New York Metropolitan Area is one of the most populous urban agglomerations in the world. New York City makes up over 40% of the population of New York State, two-thirds of the states population lives in the New York City Metropolitan Area, and nearly 40% lives on Long Island. Both the state and New York City were named for the 17th-century Duke of York, the next four most populous cities in the state are Buffalo, Rochester, Yonkers, and Syracuse, while the state capital is Albany. New York has a diverse geography and these more mountainous regions are bisected by two major river valleys—the north-south Hudson River Valley and the east-west Mohawk River Valley, which forms the core of the Erie Canal. Western New York is considered part of the Great Lakes Region and straddles Lake Ontario, between the two lakes lies Niagara Falls. The central part of the state is dominated by the Finger Lakes, New York had been inhabited by tribes of Algonquian and Iroquoian-speaking Native Americans for several hundred years by the time the earliest Europeans came to New York. The first Europeans to arrive were French colonists and Jesuit missionaries who arrived southward from settlements at Montreal for trade, the British annexed the colony from the Dutch in 1664. The borders of the British colony, the Province of New York, were similar to those of the present-day state, New York is home to the Statue of Liberty, a symbol of the United States and its ideals of freedom, democracy, and opportunity. In the 21st century, New York has emerged as a node of creativity and entrepreneurship, social tolerance. On April 17,1524 Verrazanno entered New York Bay, by way of the now called the Narrows into the northern bay which he named Santa Margherita. Verrazzano described it as a vast coastline with a delta in which every kind of ship could pass and he adds. This vast sheet of water swarmed with native boats and he landed on the tip of Manhattan and possibly on the furthest point of Long Island. Verrazannos stay was interrupted by a storm which pushed him north towards Marthas Vineyard, in 1540 French traders from New France built a chateau on Castle Island, within present-day Albany, due to flooding, it was abandoned the next year. In 1614, the Dutch under the command of Hendrick Corstiaensen, rebuilt the French chateau, Fort Nassau was the first Dutch settlement in North America, and was located along the Hudson River, also within present-day Albany. The small fort served as a trading post and warehouse, located on the Hudson River flood plain, the rudimentary fort was washed away by flooding in 1617, and abandoned for good after Fort Orange was built nearby in 1623. Henry Hudsons 1609 voyage marked the beginning of European involvement with the area, sailing for the Dutch East India Company and looking for a passage to Asia, he entered the Upper New York Bay on September 11 of that year
12.
Mint (facility)
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A mint is an industrial facility which manufactures coins that can be used in currency. The history of mints correlates closely with the history of coins, in the beginning, hammered coinage or cast coinage were the chief means of coin minting, with resulting production runs numbering as little as the hundreds or thousands. In modern mints, coin dies are manufactured in large numbers, with the mass production of currency, the production cost is weighed when minting coins. For example, it costs the United States Mint much less than 25 cents to make a quarter, metals were well suited to represent wealth, owing to their great intrinsic value and their durability, divisibility and rarity. The first mint was established in Lydia in the 7th century BC, for coining gold, silver. The Lydian innovation of manufacturing coins under the authority of the spread to neighboring Greece. Some of the earliest Greek mints were within city-states on Greek islands such as Crete, at about the same time, coins and mints appeared independently in China and spread to Korea and Japan. The manufacture of coins in the Roman Empire, dating from about the 4th century BC, the origin of the word mint is ascribed to the manufacture of silver coin at Rome in 269 BC at the temple of Juno Moneta. This goddess became the personification of money, and her name was applied both to money and to its place of manufacture, Roman mints were spread widely across the Empire, and were sometimes used for propaganda purposes. The populace often learned of a new Roman Emperor when coins appeared with the new Emperors portrait, Ancient coins were made by casting in moulds or by striking between engraved dies. The Romans cast their larger copper coins in clay moulds carrying distinctive markings, not because they knew nothing of striking, casting is now used only by counterfeiters. The most ancient coins were cast in bulletshaped or conical moulds, the blank or unmarked piece of metal was placed on a small anvil, and the die was held in position with tongs. The reverse or lower side of the received a rectangular mark made by the sharp edges of the little anvil. Subsequently the anvil was marked in ways, and decorated with letters and figures of beasts. The spherical blanks soon gave place to lenticular-shaped ones, the blank was made red-hot and struck between cold dies. One blow was usually insufficient, and the method was similar to that used in striking medals in high relief. With the substitution of iron for bronze as the material for dies, about 300 AD, in the Middle Ages bars of metal were cast and hammered out on an anvil. Portions of the sheets were then cut out with shears
