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Hallmark Records Albums
A hallmark is an official 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'' can also be used to refer to any distinguishing mark. 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. Distinguishment Hallmarks are often confused with "trademarks" or "maker's marks". A hallmark is not the mark of a manufacturer to distinguish their products from other manufacturers' products: that is the function of trademarks or makers' marks. To be a true hallmark, it must be the guarantee of an independent body or authority that the contents are as marked. Thus, a stamp of "925" by itself is not, strictly spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metal
A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typically ductile (can be drawn into wires) and malleable (they can be hammered into thin sheets). These properties are the result of the ''metallic bond'' between the atoms or molecules of the metal. A metal may be a chemical element such as iron; an alloy such as stainless steel; or a molecular compound such as polymeric sulfur nitride. In physics, a metal is generally regarded as any substance capable of conducting electricity at a temperature of absolute zero. Many elements and compounds that are not normally classified as metals become metallic under high pressures. For example, the nonmetal iodine gradually becomes a metal at a pressure of between 40 and 170 thousand times atmospheric pressure. Equally, some materials regarded as metals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
