Gold (pronounced /ˈɡoʊld/) is a chemical element A chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus. The term is also used to refer to a pure chemical substance composed of atoms with the same number of protons. Common examples of elements are iron, copper, silver, gold, hydrogen, carbon, with the symbol Au (Latin Latin is an Italic language originally spoken in Latium and Ancient Rome. Through the Roman conquest, Latin spread throughout the Mediterranean and a large part of Europe. Romance languages such as Catalan, French, Italian, Portuguese, Romanian, and Spanish are descended from Latin, while many others, especially European languages, have inherited: aurum) and an atomic number In chemistry and physics, the atomic number is the number of protons found in the nucleus of an atom and therefore identical to the charge number of the nucleus. It is conventionally represented by the symbol Z. The atomic number uniquely identifies a chemical element. In an atom of neutral charge, atomic number is equal to the number of electrons of 79. It has been a highly sought-after precious metal A precious metal is a rare, naturally occurring metallic chemical element of high economic value, which is not radioactive . Chemically, the precious metals are less reactive than most elements, have high lustre, are softer or more ductile, and have higher melting points than other metals. Historically, precious metals were important as currency, for coinage, jewelry, and other arts since the beginning of recorded history Recorded history is human history that has been written down or recorded by the use of language. It starts in the 4th millennium BC, with the invention of writing. The period before this is known as prehistory. The metal occurs as nuggets A gold nugget is a naturally occurring piece of native gold. Watercourses often concentrate the nuggets and they are recovered by placer mining, but they may also be found in residual deposits where the gold-bearing veins or lodes have decayed. Nuggets are also found in the tailings piles of previous mining operations, especially those left by or grains in rocks, in veins In geology, a vein is a finite volume within a rock, having a distinct shape, filled with crystals of one or more minerals, which were precipitated from an fluid. Veins are formed by fluids carrying mineral constituents into a rock mass as a consequence of some form of hydraulic flow within the rock. Usually this is the result of hydrothermal and in alluvial deposits Alluvium is loose, unconsolidated (not cemented together into a solid rock), soil or sediments, eroded, deposited, and reshaped by water in some form in a non-marine setting. Alluvium is typically made up of a variety of materials, including fine particles of silt and clay and larger particles of sand and gravel. When this loose alluvial material. Gold is dense, soft, shiny and the most malleable Ductility is a mechanical property used to describe the extent to which materials can be deformed plastically without fracture and ductile Ductility is a mechanical property used to describe the extent to which materials can be deformed plastically without fracture pure metal known. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. It is one of the coinage metals A Group 11 element is one in the series of elements in group 11 in the periodic table, consisting of transition metals which are the traditional coinage metals of copper (Cu), silver (Ag), and gold (Au). Roentgenium (Rg) belongs to this group of elements based on its electronic configuration, but cannot be considered coinage metal (short lived and formed the basis for the gold standard The gold standard is a monetary system in which a region's common medium of exchange are paper notes that are normally freely convertible into pre-set, fixed quantities of gold. The gold standard is not currently used by any government, having been replaced completely by fiat currency.[citation needed] used before the collapse of the Bretton Woods system The Bretton Woods system of monetary management established the rules for commercial and financial relations among the world's major industrial states in the mid 20th century. The Bretton Woods system was the first example of a fully negotiated monetary order intended to govern monetary relations among independent nation-states in 1971.
At the end of 2006, it was estimated that all the gold ever mined totaled 158,000 tonnes.[1] This can be represented by a cube with an edge length of just 20.2 meters. Modern industrial uses include dentistry Dentistry is the known evaluation, diagnosis, prevention, and treatment of diseases, disorders and conditions of the soft and hard tissues of the jaw , the oral cavity, maxillofacial area and the adjacent and associated structures and their impact on the human body. Dentistry is a part of stomatology. Dentistry is widely considered necessary for and electronics Electronics is a branch of science and technology that deals with the controlled flow of electrons. The ability to control electron flow is usually applied to information handling or device control. Electronics is distinct from electrical science and technology, which deals with the generation, distribution, control and application of electrical, where gold has traditionally found use because of its good resistance to oxidative Redox describes all chemical reactions in which atoms have their oxidation number (oxidation state) changed. This can be either a simple redox process such as the oxidation of carbon to yield carbon dioxide or the reduction of carbon by hydrogen to yield methane (CH4), or it can be a complex process such as the oxidation of sugar in the human body corrosion and excellent quality as a conductor of electricity.
Chemically, gold is a transition metal The name transition comes from their position in the periodic table of elements. In each of the four periods in which they occur, these elements represent the successive addition of electrons to the d atomic orbitals of the atoms. In this way, the transition metals represent the transition between group 2 elements and group 13 elements and can form trivalent and univalent In chemistry, valence, also known as valency or valency number, is a measure of the number of chemical bonds formed by the atoms of a given element. Over the last century, the concept of valence evolved into a range of approaches for describing the chemical bond, including Lewis structures , valence bond theory (1927), molecular orbitals (1928), cations An ion is an atom or molecule where the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. An anion , from the Greek word ἀνά (ana), meaning 'up', is an ion with more electrons than protons, giving it a net negative charge (since electrons are negatively charged and upon solvation. Compared with other metals, pure gold is more chemically unreactive, but it is attacked by aqua regia Aqua regia or aqua regis is a highly corrosive, fuming yellow or red solution, also called nitro-hydrochloric acid. The mixture is formed by freshly mixing concentrated nitric acid and concentrated hydrochloric acid, usually in a volumetric ratio of 1:3 respectively. It was so named because it can dissolve the so-called "royal metals," (a mixture of acids), forming chloroauric acid Chloroauric acid is a inorganic compound with the formula HAuCl4. It is commonly used as a precursor to gold in a variety of purposes. The term chloroauric acid is also sometimes used to describe other gold chlorides, and by alkaline solutions of cyanide A cyanide is any chemical compound that contains the cyano group , which consists of a carbon atom triple-bonded to a nitrogen atom. Inorganic cyanides are generally salts of the anion CN-. Organic compounds that have a -C≡N functional group are called nitriles. Of the many kinds of cyanide compounds, some are gases; others are solids or liquids but not by single acids such as hydrochloric Hydrochloric acid is the solution of hydrogen chloride (H , nitric Colorless when pure older samples tend to acquire a stronger yellow cast due to the accumulation of oxides of nitrogen. If the solution contains more than 86% nitric acid, it is referred to as fuming nitric acid. Fuming nitric acid is characterized as white fuming nitric acid and red fuming nitric acid, depending on the amount of nitrogen dioxide or sulfuric acids Sulfuric acid, H2SO4, is a strong mineral acid. It is soluble in water at all concentrations. Sulfuric acid has many applications, and is one of the top products of the chemical industry. World production in 2001 was 165 million tonnes, with an approximate value of US$8 billion. Principal uses include lead-acid batteries for cars and other. Gold dissolves in mercury Mercury , also called quicksilver (/ˈkwɪksɪlvər/) or hydrargyrum (/haɪˈdrɑrdʒɨrəm/ hye-DRAR-ji-rəm), is a chemical element with the symbol Hg (Latinized Greek: hydrargyrum, meaning watery or liquid silver) and atomic number 80. A heavy, silvery d-block metal, mercury is one of six chemical elements that are liquid at or near room, forming amalgam An amalgam is a substance formed by the reaction of some other substance with mercury. Almost all metals can form amalgams with mercury, notable exceptions being iron and platinum. Silver-mercury amalgams are important in dentistry, and gold-mercury amalgam is used in the extraction of gold from ore alloys, but does not react with it. Since gold is insoluble in nitric acid Colorless when pure older samples tend to acquire a stronger yellow cast due to the accumulation of oxides of nitrogen. If the solution contains more than 86% nitric acid, it is referred to as fuming nitric acid. Fuming nitric acid is characterized as white fuming nitric acid and red fuming nitric acid, depending on the amount of nitrogen dioxide which will dissolve silver and base metals In chemistry, the term base metal is used informally to refer to a metal that oxidizes or corrodes relatively easily, and reacts variably with diluted hydrochloric acid to form hydrogen. Examples include iron, nickel, lead and zinc. Copper is considered a base metal as it oxidizes relatively easily, although it does not react with HCl. It is, this is exploited as the basis of the gold refining Refining consists of purifying an impure material, in this case a metal. It is to be distinguished from other processes such as smelting and calcining in that those two involve a chemical change to the raw material, whereas in refining, the final material is usually identical chemically to the original one, only it is purer. The processes used are technique known as "inquartation and parting". Nitric acid has long been used to confirm the presence of gold in items, and this is the origin of the colloquial term "acid test", referring to a gold standard test for genuine value.
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ElmerFusterpuck
Sat, 28 Nov 2009 16:10:39 GM
I was chasing . gold. type earlier this decade when . gold. was around $350 to $400 an ounce. Hindsight says I should have chased the $20's some more, but I'
Q. Hi, I would like to know your opinions on what type of gold you believe compliments (or matches) a black onyx stone best - Yellow Gold or White Gold? I am purchasing a "class ring" and am still unsure of whether 14k white or yellow goes looks best with the stone. Thanks for your opinions.
Asked by Kevin - Mon Oct 5 20:55:11 2009 - - 1 Answers - 0 Comments
A. I am a jeweler and My preference is yellow gold, with white gold people will often say " lovely silver ring", but if the silver look is your style then White Gold is best as it is harder wearing and stronger than silver. Rose gold is also OK. Black onyx is complimented by most colors. Don't skimp on the gold. Solid is better than a cheaper hollow ring.
Answered by mrcoins.australia - Sat Oct 10 16:10:36 2009
