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Hallmark
A hallmark is an official Mark (sign), mark or series of marks struck on items made of metal, mostly to certify the content of noble metals—such as platinum, gold, silver and in some nations, palladium. In a more general sense, the term ''Wiktionary:hallmark, hallmark'' is used to refer to any standard of quality. Not to be confused with responsibility marks that are the marks of the maker. General overview Historically, hallmarks were applied by a trusted party: the "guardians of the craft" or, more recently, by an assay office (). Hallmarks are a guarantee of certain purity or fineness of the metal, as determined by official metal (assay) testing. Hallmarks include information not only about the precious metal and fineness, but the country from which the item was tested and marked. Some hallmarks can reveal even more information, e.g. the assay office, size of the object marked, year the item was hallmarked - referred to as a (also known as date letter). Distinguishment Ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Assay Office
Assay offices are institutions set up to assay (test the purity of) precious metals. This is often done to protect consumers from buying fake items. Upon successful completion of an assay (i.e. if the metallurgical content is found be equal or better than that claimed by the maker and it otherwise conforms to the prevailing law) the assay offices typically stamp a hallmark on the item to certify its metallurgical content. Hallmarking first appeared in France, with the Goldsmiths' Statute of 1260 promulgated under Étienne Boileau, Provost of Paris, for King Louis IX. US assay offices Title 15, Chapter 8, Section 291 of the United States Code makes it unlawful to stamp goods in the United States with "United States assay" or any similar stamp which gives the impression that the item has been officially assayed by the United States government. General overview and function of U.S. assay offices Assay offices did and do exist in the U.S., but they are affiliated with the governm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metallurgical Assay
A metallurgical assay is a compositional analysis of an ore, metal, or alloy, usually performed in order to test for purity or quality. Some assay methods are suitable for raw materials; others are more appropriate for finished goods. Raw precious metals (bullion) are assayed by an assay office. Silver is assayed by titration, gold by cupellation and platinum by inductively coupled plasma optical emission spectrometry (ICP OES). Precious metal items of art or jewelry are frequently hallmarked (depending upon the requirements of the laws of either the place of manufacture or the place of import). Where required to be hallmarked, semi-finished precious metal items of art or jewelry pass through the official testing channels where they are analyzed or assayed for precious metal content. While different nations permit a variety of legally acceptable finenesses, the assayer is actually testing to determine that the fineness of the product conforms with the statement or claim of f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sterling Silver
Sterling silver is an alloy composed mass fraction (chemistry), by weight of 92.5% silver and 7.5% other metals, usually copper. The sterling silver silver standards, standard has a minimum millesimal fineness of 925. ''Fineness, Fine silver'', which is 99.9% pure silver, is relatively soft, so silver is usually alloyed with copper to increase its hardness and strength. Sterling silver is prone to Tarnish, tarnishing, and elements other than copper can be used in alloys to reduce tarnishing, as well as casting porosity and firescale. Such elements include germanium, zinc, platinum, silicon, and boron. Recent examples of these alloys include Argentium sterling silver, ''argentium'', ''sterlium'' and ''silvadium''. Etymology The term ''sterling silver'' originally meant "silver fit to be used in the making of sterlings", ''sterling'' being another name for the English Penny (English coin), silver penny. The etymology of ''sterling'' itself is Pound_sterling#Etymology, unclear and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Byzantine
The Byzantine Empire, also known as the Eastern Roman Empire, was the continuation of the Roman Empire centred on Constantinople during late antiquity and the Middle Ages. Having survived the events that caused the fall of the Western Roman Empire in the 5th centuryAD, it endured until the fall of Constantinople to the Ottoman Empire in 1453. The term 'Byzantine Empire' was coined only after its demise; its citizens used the term 'Roman Empire' and called themselves 'Romans'. During the early centuries of the Roman Empire, the western provinces were Latinised, but the eastern parts kept their Hellenistic culture. Constantine I () legalised Christianity and moved the capital to Constantinople. Theodosius I () made Christianity the state religion and Greek gradually replaced Latin for official use. The empire adopted a defensive strategy and, throughout its remaining history, experienced recurring cycles of decline and recovery. It reached its greatest extent un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metal
A metal () is a material that, when polished or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, electricity and thermal conductivity, heat relatively well. These properties are all associated with having electrons available at the Fermi level, as against nonmetallic materials which do not. Metals are typically ductile (can be drawn into a wire) and malleable (can be shaped via hammering or pressing). A metal may be a chemical element such as iron; an alloy such as stainless steel; or a molecular compound such as polythiazyl, polymeric sulfur nitride. The general science of metals is called metallurgy, a subtopic of materials science; aspects of the electronic and thermal properties are also within the scope of condensed matter physics and solid-state chemistry, it is a multidisciplinary topic. In colloquial use materials such as steel alloys are referred to as metals, while others such as polymers, wood or ceramics are nonmetallic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mark (sign)
A mark is a written or imprinted symbol used to indicate some trait of an item, for example, its ownership or maker. Mark usually consists of letters, numbers, words, and drawings. Inscribing marks on the manufactured items was likely a precursor of communicative writing. Historically, the marks were used for few purposes: * declaration of the ''ownership'' (an ownership mark, for example, livestock branding); * ''identification'' of the manufacturer and place of origin (''manufacturer's mark'', ''maker's mark'', later a factory mark); * ''differentiation'' in order to distinguish between similar items (for example, a date mark). These marks are typically useful to Distribution (marketing), distributors; * ''certification'' of the product quality (certification mark, for example, an assay mark). In the 17th century in the English cloth trade a new class of marks was created, now called trademarks: the cloth was required to contain both the Silver hallmarks#United_Kingdom_and_Ire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palladium
Palladium is a chemical element; it has symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1802 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas (formally 2 Pallas), which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form together a group of elements referred to as the platinum group metals (PGMs). They have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium and its congener platinum is used in catalytic converters, which convert as much as 90% of the harmful gases in automobile exhaust (hydrocarbons, carbon monoxide, and nitrogen dioxide) into nontoxic substances (nitrogen, carbon dioxide and water vapor). Palladium is also used in electronics, dentistry, medicine, hydrogen purification ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carat (purity)
The fineness of a precious metal object (coin, bar, jewelry, etc.) represents the weight of ''fine metal'' therein, in proportion to the total weight which includes alloying base metals and any impurities. Alloy metals are added to increase hardness and durability of coins and jewelry, alter colors, decrease the cost per weight, or avoid the cost of high-purity refinement. For example, copper is added to the precious metal silver to make a more durable alloy for use in coins, housewares and jewelry. Coin silver, which was used for making silver coins in the past, contains 90% silver and 10% copper, by mass. Sterling silver contains 92.5% silver and 7.5% of other metals, usually copper, by mass. Various ways of expressing fineness have been used and two remain in common use: ''millesimal fineness'' expressed in units of parts per 1,000 and '' karats'' or ''carats'' used only for gold. Karats measure the parts per 24, so that 18 karat = = 75% gold and 24 karat gold is considere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Factory Mark
A factory mark is a marking affixed by manufacturers on their productions in order to authenticate them. Numerous factory marks are known throughout the ages, and are essential in determining the provenance or dating of productions. History The manufacturer's marks are very old: the ones found on Korakou culture pottery are four thousand years old, and the ones on ancient Greek and Roman vases date back to 5th-4th centuries BC. While the production marks are technically distinct from the ownership marks, at these times, when a craftsman typically was the same person as the merchant, and many people were illiterate, a single mark frequently served both purposes. Medieval gilds set up the system of compulsory ("regulatory") marks for the craftsman, intended to trace the defective items and punish the offenders, with most typical examples provided by the bakery trade. In English weapons manufacturing (including cutlery) the regulations concerning the manufacturer marks were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jewelry Hallmark
Jewellery (or jewelry in American English) consists of decorative items worn for personal adornment such as brooches, rings, necklaces, earrings, pendants, bracelets, and cufflinks. Jewellery may be attached to the body or the clothes. From a western perspective, the term is restricted to durable ornaments, excluding flowers for example. For many centuries metal such as gold often combined with gemstones, has been the normal material for jewellery, but other materials such as glass, shells and other plant materials may be used. Jewellery is one of the oldest types of archaeological artefact – with 100,000-year-old beads made from ''Nassarius'' shells thought to be the oldest known jewellery. The basic forms of jewellery vary between cultures but are often extremely long-lived; in European cultures the most common forms of jewellery listed above have persisted since ancient times, while other forms such as adornments for the nose or ankle, important in other cultures, are muc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gold
Gold is a chemical element; it has chemical symbol Au (from Latin ) and atomic number 79. In its pure form, it is a brightness, bright, slightly orange-yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal, a group 11 element, and one of the noble metals. It is one of the least reactivity (chemistry), reactive chemical elements, being the second-lowest in the reactivity series. It is solid under standard temperature and pressure, standard conditions. Gold often occurs in free elemental (native state (metallurgy), native state), as gold nugget, nuggets or grains, in rock (geology), rocks, vein (geology), veins, and alluvial deposits. It occurs in a solid solution series with the native element silver (as in electrum), naturally alloyed with other metals like copper and palladium, and mineral inclusions such as within pyrite. Less commonly, it occurs in minerals as gold compounds, often with tellurium (gold tellurides). Gold is resistant to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
