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Doré Bar
A doré bar is a semi-pure alloy of gold and silver. It is usually created at the site of a mine and then transported to a refinery for further purification. The proportions of silver and gold can vary widely. Doré bars weigh as much as 25 kg. During the 19th century gold rushes, gold nuggets and dust were melted into crude gold bars mistakenly called "bullion" by miners. They were, more accurately, doré bars with higher contents of silver and other adulterants than the mints would accept. Mint and private assayers would subsequently refine the doré bars to an acceptable purity, 999 fine, gold bullion, with the silver and base metals removed. By the time of the California gold rush, mints were moving away from the age-old process of cupellation to " part" bullion and moving toward the acid refining process developed by chemist Joseph Louis Gay-Lussac for the French mint. By the time of the Klondike gold rush, mints were replacing Gay-Lussac's acid process and introdu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Alloy
An alloy is a mixture of chemical elements of which in most cases at least one is a metal, metallic element, although it is also sometimes used for mixtures of elements; herein only metallic alloys are described. Metallic alloys often have properties that differ from those of the pure elements from which they are made. The vast majority of metals used for commercial purposes are alloyed to improve their properties or behavior, such as increased strength, hardness or corrosion resistance. Metals may also be alloyed to reduce their overall cost, for instance alloys of gold and Copper(II) sulfate, copper. A typical example of an alloy is SAE 304 stainless steel, 304 grade stainless steel which is commonly used for kitchen utensils, pans, knives and forks. Sometime also known as 18/8, it as an alloy consisting broadly of 74% iron, 18% chromium and 8% nickel. The chromium and nickel alloying elements add strength and hardness to the majority iron element, but their main function is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
United States Census Bureau
The United States Census Bureau, officially the Bureau of the Census, is a principal agency of the Federal statistical system, U.S. federal statistical system, responsible for producing data about the American people and American economy, economy. The U.S. Census Bureau is part of the United States Department of Commerce, U.S. Department of Commerce and its Director of the United States Census Bureau, director is appointed by the president of the United States. Currently, Ron S. Jarmin is the acting director of the U.S. Census Bureau. The Census Bureau's primary mission is conducting the United States census, U.S. census every ten years, which allocates the seats of the United States House of Representatives, U.S. House of Representatives to the U.S. state, states based on their population. The bureau's various censuses and surveys help allocate over $675 billion in federal funds every year and it assists states, local communities, and businesses in making informed decisions. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ore Genesis
Various theories of ore genesis explain how the various types of mineral deposits form within Earth's crust. Ore-genesis theories vary depending on the mineral or commodity examined. Ore-genesis theories generally involve three components: source, transport or conduit, and trap. (This also applies to the petroleum industry: petroleum geologists originated this analysis.) *''Source'' is required because metal must come from somewhere, and be liberated by some process. *''Transport'' is required first to move the metal-bearing fluids or solid minerals into their current position, and refers to the act of physically moving the metal, as well as to chemical or physical phenomena which encourage movement. *''Trapping'' is required to concentrate the metal via some physical, chemical, or geological mechanism into a concentration which forms mineable ore. The biggest deposits form when the source is large, the transport mechanism is efficient, and the trap is active and ready at the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Gold Mining
Gold mining is the extraction of gold by mining. Historically, mining gold from Alluvium, alluvial deposits used manual separation processes, such as gold panning. The expansion of gold mining to ores that are not on the surface has led to more complex extraction processes such as pit mining and gold cyanidation. In the 20th and 21st centuries, most volume of mining was done by large corporations. However, the value of gold has led to millions of small, Artisanal mining, artisanal miners in many parts of the Global South. Like all mining, Mining#Human rights, human rights and Environmental effects of mining, environmental issues are common in the gold mining industry, and can result in environmental conflict. In mines with less regulation, health and safety risks are much higher. History The exact date that humans first began to mine gold is unknown, but some of the oldest known gold artifacts were found in the Varna Necropolis in Bulgaria. The graves of the necropolis were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Gold Extraction
Gold extraction is the extraction of gold from dilute ores using a combination of chemical processes. Gold mining produces about 3600 tons annually, and another 300 tons is produced from recycling. Since the 20th century, gold has been principally extracted in a cyanide process by leaching the ore with cyanide solution. The gold may then be further refined by gold parting, which removes other metals (principally silver) by blowing chlorine gas through the molten metal. Historically, small particles of gold were amalgamated with mercury, and then concentrated by boiling away the mercury. The mercury method is still used in some small operations. Types of ore Gold occurs principally as a native metal, i.e., gold itself. Sometimes it is alloyed to a greater or lesser extent with silver, which is called electrum. Native gold can occur as sizeable nuggets, as fine grains or flakes in alluvial deposits, or as grains or microscopic particles (known as colour) embedded in rock min ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Gold Bar
A gold bar, also known as gold bullion or a gold ingot, is a quantity of refined metallic gold that can be shaped in various forms, produced under standardized conditions of manufacture, labeling, and record-keeping. Larger varieties of gold bars, produced by casting molten metal into molds, are called ingots. Smaller bars are often created through minting or stamping from rolled gold sheets. Central banks typically hold the standard Good Delivery gold bar in their gold reserves and it is widely traded among bullion dealers. Additionally, the kilobar, weighing , and the gold bar are popular for trading and investment due to their more manageable size and weight. These bars carry a minimal premium over the spot price of gold, facilitating small transfers between banks and traders. While most kilobars have a flat appearance, a preference for brick-shaped bars exists among some investors, particularly in Europe. Types Gold bars are classified based on their production pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Electrum
Electrum is a naturally occurring alloy of gold and silver, with trace amounts of copper and other metals. Its color ranges from pale to bright yellow, depending on the proportions of gold and silver. It has been produced artificially and is also known as "Colored gold#Green gold, green gold".Emsley, John (2003Nature's building blocks: an A–Z guide to the elements Oxford University Press. p. 168. . Electrum was used as early as the third millennium BC in the Old Kingdom of Egypt, sometimes as an exterior coating to the pyramidion, pyramidia atop ancient Egyptian pyramids and obelisks. It was also used in the making of ancient Beaker (archaeology) , drinking vessels. The first known metal coins made were of electrum, dating back to the end of the 7th century or the beginning of the 6th century BC. Etymology The name ''electrum'' is the Latinized form of the Greek language, Greek word ἤλεκτρον (''ḗlektron''), mentioned in the ''Odyssey'', referring to a metallic s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Bullion Coin
A bullion coin (also known as a specie) is a coin struck from highly refined precious metal (bullion) and kept as a store of value or an investment rather than used in day-to-day commerce, or collectable, with numismatic value beyond that of its metal content. A bullion coin is distinguished by its weight (or mass) and fineness on the coin. Unlike rounds, bullion coins are minted by government mints and have a legal tender face value. Bullion coins can have fineness ranging from 91.9% (22 karat) to 99.99% purity (24 karat). In the United Kingdom coins deemed to be investment coins are exempt from value-added tax (VAT) on transactions. A coin is considered to be an investment coin if it was minted after 1800, and at least 900 thousandths fine, and has been legal tender in its country of origin, and not normally sold at more than 180% of the value of its precious metal content; or if it is on a long list of coins deemed to be investment coins. This Web page links to the current list ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Bullion
Bullion is non-ferrous metal that has been refined to a high standard of elemental purity. The term is ordinarily applied to bulk metal used in the production of coins and especially to precious metals such as gold and silver. It comes from the Anglo-Norman term for a melting-house where metal was refined, and earlier from French , "boiling". Although precious metal bullion is no longer used to make coins for general circulation, it continues to be held as an investment with a reputation for stability in periods of economic uncertainty. To assess the purity of gold bullion, the centuries-old technique of fire assay is still employed, together with modern spectroscopic instrumentation, to accurately determine its quality. As investment The specifications of bullion are often regulated by market bodies or legislation. In the European Union, the minimum purity for gold to be referred to as "bullion", which is treated as investment gold with regard to taxation, is 99.5% for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
NAICS
The North American Industry Classification System or NAICS () is a classification of business establishments by type of economic activity (the process of production). It is used by governments and business in Canada, Mexico, and the United States of America. It has largely replaced the older Standard Industrial Classification (SIC) system, except in some government agencies, such as the U.S. Securities and Exchange Commission (SEC). An establishment is typically a single physical location, though administratively distinct operations at a single location may be treated as separate establishments. Each establishment is classified as an industry according to the primary business activity taking place there. NAICS does not offer guidance on organizing enterprises (companies) composed of multiple establishments. Codes The NAICS numbering system employs a five or six-digit code at the most detailed industry level. The first five digits are generally (although not always strictly) t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
