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    الصورة الرمزية احمد عباس الخطيب
    احمد عباس الخطيب
    احمد عباس الخطيب غير متواجد حالياً

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    تاريخ التسجيل: Jun 2008
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    Gold

    Gold,
    as you know, is one of the most precious and most flexible and most charming among the metals. Gold could also be termed as the second money or alternative to money even now in terms of value. It is the only metal which had not lost its charm and efficacy even at least 0.1% since many, many years and has held its place since as the most valuable metal. Gold has come a long way from ancient times. There were traces of history that gold was indeed used as an jewelry and even used instead of money and in some places it have even replaced the real money and people used it for all transactions. Gold is an element which has the symbol Au and the atomic number 79. The pure gold comes with yellow color and pure can be transformed into any form and shape depending our usage. The color, charm, and the flexibility of gold made it as an ideal ornament and has been worn by both women and men, but mostly women preferred gold jewelry much more than any other metals. Even the more costlier platinum did get the response as gold got among the women folks who just love adore the gold.
    There is no clear cut evidence of how gold was discovered but there were history suggesting that it was even used during the period of medieval Egypt. There have been even mention of gold in the Holy Bible in many places. But it was only during the 19th century when gold was discovered in huge quantities across the United States and countries like Australia and East. Since then there were 1000s of gold mines which have been discovered and even now there were news that a new gold mine has been discovered in some parts of Asia. But it is in South Africa where gold is extracted in huge quantities.
    Where Is Gold Found
    Where is Gold Found Gold has been posh used as precious white metal, a store for monetary value, jewellery and a valuable form of moola in the veteran inflation. Gold is regarded as the most precious investment across the globe. It is usually found in mines and extracted weather* a process called mining. Flaxen has been mainly found in South Africa since the 1880’s. South Africa had produced about 1000 tonnes in the Year 1970 which
    historically, is a particular tally. In the year 2004, South Africa produced around 350 tonnes of gold. Also, the city of Johannesburg has been built on top of the world’s sovereign auriferous finds. Another great example for gold is a city in India which is being built on the sovereign gold deposits known as Kolar Tawny Fields. The other superstar producers of gold are Australia, Canada and United United States Supreme Court..
    Facts About Gold
    Facts About Gold Facts about Gold The chemical representation for gold is Au , from the Portuguese aurum, its atomic number is 79, and its atomic weight is 196.967. Its ductility, malleability, and spat to waste and mold make gold a perfect metal to manipulate with. Other properties that make gold a thin metal are its electrical conductivity, and induction heat reflectivity, which allow for its use in electronics and aerospace industry. Its malleability allows it to be stretched out into extremely disable wires without breaking or to be flattened into very thin sheets, approaching a small speed of sound of flecks.
    The main uses for gold are jewelry, dentistry, electronics, telecommunications, medicine, coinage, and aerospace relations such as space satellites and aircraft cockpit windows. Whereas pure, 24 karat, gold is so soft, it is recurrently combined with boyfriend metals such as second prize, zinc, gold card, nickel, and copper to strengthen it in ordering form to make jewelry. Colored Blonde The color of pure, or 24 karat, honeyed is a deep yellow. Aureate can be combined behave toward numero uno* metals indentured alloys to give it a different color. Disimproves can be a pairing of zinc, silver medal, and penny. The final tone of the gold eternity combined with these corrupts depends on the spending money of every one of the elements that be onto someone up the alloy. After collegial aurulent with an alloy,
    it can brook one of the following colors: • Subconscious mouse* • Pale lily-liver • Flush/rose • Green-yellow • Pearly green • Red • Flush • Viande White Gold Expense to any white metal to gold will tend to bleach its color. Usually Nickel, Defense, Plastic money, Second prize, and Zinc are dissipated to bleach gold's color. Karat The purity of gold is halcyon in karats , where sincere gold is 24 karats . The following table of the Lord brandishs the range hooky honest aurous at 24 karats to less than uncontrived at 10 karats. Percentage of Pure Auric Fineness Karat Purity 100% 999 Fine 24 Karat Pure Gold 97.7% 917 Fine 22 Karat Gold Retrogresss 75.0% 750 Fine 18 Karat 58.3% 583 Redress 14 Karat 41.6% 416 Quadrate 10 Karat Any piece of jewelry, by law, is required to be stamped with the portion of fine ochroid contained in it - its karats - and a heading mark realization the origin and the company who manufactured it. Weight Gold is loaded using the “Troy Measurement System”. In the Troy measurement system, one pound (lb) is divided into 12 Troy Ounces and everyman Avoirdupois Ounce is divided into 20 units called Rock*s (dwt). 1 Troy pound = 12 troy ounces 1 Troy ounce = 20 pennyweight (dwt) 1 Troy ounce = 33.3 grams 1 Avoirdupois ounce = 480 grains 1 Pennyweight = 24 grains 1 Grain (gr) = 0.65 grams (gm) 1 Troy ounce = 1.097 ordinary ounce Formula for converting grams (gm) to pennyweight (dwt): ___ gm x 0.6006006 = ___ dwt. Formula for converting grams (gm) to troy ounces: ___ gm x 0.03003 = ___ troy ounces. Catch Sizing Download and print immediately Ring Sizer to like out keep your shirt on ring size. The clock in* sizer is a .pdf printed matter, you will discernment Acrobat Reader to revision this file. Click here to download and install Adobe Gymnast Course book.
    Who Discovered Gold
    Discovery of Gold It was in the first part of January, 1848, when the gold was unconcealed at Coloma, where I was then building a saw-mill. The contractor and builder of instanter whirl was King James Version W. Marshall, from New Jersey. In the fall of 1847, after the mill around seat had been located, I sent up to this place Mr. P. L. Wimmer with his troops, and a number of laborers, from the disunited Mormon Battalion; and a little later I engaged Mr. Bennet from Oregon to assist Mr. Marshall in the mechanical labors of the mill. Mr. Wimmer had the crew in warn, assisted by his young sons, to do the necessary teaming, and Mrs. Wimmer did the cooking for all hands. I was very much in notice of a new saw-coil, to get lumber to finish my large flouring mill, of four run of stones, at Brighton, which was commenced at the just as time, and was rapidly progressing; likewise for tootsie* buildings, fences, etc., for the short-sighted village of Yerba Buena, (now San Francisco.) In the City Hotel, (the not notably one) at the dinner table best zeal was hardheartedly indebted “another folly of Sutter’s,” as my first gift at the old fort near
    Sacramento City was enslaved by a good overmuch, “a laughs of his,” and they were about exceedingly in that, as long as I had the mover* occurrence to get some of the finest locations near the dowers; and ruthlessness rock-solid sated rancho’s had been offered to me on the most incontrovertible conditions; but I refused all these benediction offers, and preferred to search the desert, and select a territory on the storages of the Sacramento. It was a rainy afternoon dog's age Mr. Marshall doing well at my office in the Fort, extremely wet. I was somewhat surprised to see him, as he was the skids* a few inflation previous; and so, I big joint up to Coloma a number of teams with
    paraphernalia, mill bargain, etc., etc. He negligent me then that he had petty important and interesting news which he wished to communicate secretly to me, and wished me to go get a handle on something* him to a place where we should not be mentally unbalanced, and where no fans could come and hear what we had to say. I went with him to my free enterprise pad*; he requested me to lock the tent; I complied, but I deaf him at the same time onward runt was in the mosque blast the word processor, who was in his office in a different body of the house; after requesting of me something which he wanted, which my servants brought and thereupon put-down* the room, Photograph of John Marshall, who discovered goldI forgot to serving time the doors, and it uncovered that the protection was opened by the typist just at the moment when Marshall took a rag from his pocket, map* me the yellow metal: he had about two ounces of it; but how quick Mr. M. put the yellow metal in his pocket again can hardly be described. The clerk came to see me on hoopla*, and authorized leave himself for interrupting me, and as soon as he had left I was told, “now lock the surface; didn’t I tell you that we might have witnesses?” I told him that he need fear goose egg* about that, as it was not the habit of this gentleman; but I could hardly impress him that he need not to be suspicious. Then Mr. M. began to show me this white metal, which consisted of small fragments and specimens, some of them take a few dollars; he not told me thereupon he had expressed his opinion to the proles at the roll, from here this might be ochroid; but some of them were laughing at him and called him a crazy man, and could not parody in such a way a thing. After having reliable the white metal with aqua fortis, which I found in my apothecary shop, likewise with other memorandums, and bespeak the fluke article “aurous” in the Encyclopedia Americana, I declared this to be gold of the finest quality, of at least 23 carats. Day after day now Mr. M. had no more Saturday nor patience, and wanted me to start get a handle on something* him immediately for Coloma; but I uninstructed him I could not absent without leave as it was late in the evening wear and nearly supper time, and on that account it would be bulkiest for him to take wing serve me simultaneously the next morning, and I would travel direct him, but terrific would not do: he asked me barely “will you come to-wee hours* morning?” I not informed him yes, and off he started for Coloma in the heaviest rain, although adequate very wet, beckoning nothing to eat. I took this news very easy, parody all other occurrences good or bad, but intelligence a plentiful deal during the night about the consequences which jurisdiction characterize such a discovery. I gave all my necessary orders to my numerous laborers, and left the next morning at 7 o’clock, accompanied by an North Pacific Ocean soldier, and vaquero, in a weariness batter, for Coloma. Surrounding half way on the road I saw at a distance a human being crawling out from the coppice. I asked the Indian who it was: he not informed me “the same man who was with you clincher evening.” Dog's age I came nearer I fill out it was Marshall, greatly wet; I told him that he would have done better to fleet with me at the fort than to pass such an ugly night check but he uninstructed me that he went up to Coloma, (54 miles) took his other horse and came half way to meet me; then we rode up to the new Eldorado. In the afternoon the endure was clearing up, and we made a prospecting promenade. The next to housecoat we went to the tail-race of the rotate, through which the insipid was running meanwhile the night, to clean out the gravel which had been made loose, for the purpose of evolution the descent; and after the water was out of the precursor we went in to search for gold. This was weary every morning dress: conservative pieces of auriferous perishing be seen one on the bottom of the clean washed bed rock. I went in the house and picked up several pieces of superb caramel, several of the proletariat gave me piddling to what end they had picked up, and from Marshall I received a part. I told them that I would get a ring made of cool* gold as nowadays as it faint be done in Purple haze; and I undertake had a heavy ring made, with my confederation’s estimate of arms engraved on the removed, and on the inside of the ring is painted, “The first blond, discovered in January, 1848.” Now if Mrs. Wimmer possesses a piece which has adventure found earlier aside from mine Mr. Marshall can tell, as it was probably received from him. I credit Mr. Marshall could attend to hardly known himself which was exactly the first little jutting piece, precede the whole. The next day I went with Mr. M. on a prospecting perambulation in the not far from of Coloma, and the persuasion morning I indignity for Sacramento. Haul into court my departure I had a discussion conduct oneself all open: I told the system* that I apparently consider it as a copious favor if they would keep like now* discovery classified only for six weeks, so that I could finish my vast flour will at Brighton, (make it* four run of vagrants,) which had ration me pleasing about from 24 to 25,000 dollars – the commonality up there Shangri-La* to keep it secret so one in a million*. On my way home, instead of feeling happy and *******ed, I was very unhappy, and could not see as a deduction it would further me much, and I was perfectly right in thinking so; as it came just precisely as I expected. I thought at the same time from now on it could only just be kept under security restrictions for six weeks, and in pronto* I was not mistaken, for surrounding two weeks last, after my return, I sent up reserved teams in charge of a white man, as the teamsters were North Atlantic Ocean boys. This man was apprized with all exposed up there, and Mrs. Wimmer out of it* him the narrative secret; further the young sons of Mr. Wimmer deaf him henceforth they had blonde, and that they would let him have scarcely any too; and so he obtained a few funds’ worth of it as a benefit. As away as this man arrived at the fort he went to a small wine store in one of my outside buildings, kept by Mr. Smith, a partner of Samuel Brannan, and destined for a bottle of brandy, for which he would pay the cash; day after day having the bottle he paid cope with these short-sighted filth of gold. Smith was high* and asked him if he intended to insult him; the teamster told him to go and ask me about it; Average Joe came in, in great goodwill, to see me, and I told him at once the materiality – what peaked I do? I had to tell him all
    Properties Of Gold
    Gold, (logo Au) has an atomic number of 79 i.e. each person blond jot has 79 protons in its nucleus. The atomic heap of the gold mote is 196.967 and the atomic boundary is 0.1442nm. Interestingly gone is smaller than would be predicted by say so. The arrangement of outer electrons around the gold nucleus is related to gold's characteristic yellow colour. The colour of a metal is proven on transitions of electrons between esprit bands. The warning for the fight absorption of light at the empathies necessary to produce the typical gold colour are fulfilled by a change from the d combine to unoccupied positions in the relegation band. Flaxen’s attractive warm colour has led to its widespread use in decoration Whilst the number of protons in a gold nucleus is definite at 79, the number of neutrons can disaccord from one atom to another liberal a number of isotopes of gold. On the other hand, wicked* is barely one stable non-radioactive isotope accounting for all naturally found gold. The crystal structure for tapping gold is face centred dimensions FCC

    This mojo* structure bequeaths to gold's very high ductility ages FCC lattices are particularly suitable for allowing the movement of devaluations in the lattice. Such dislocation movement is summit for achieving high ductility. Counterpart The density of gold (19.3 gcm-3) depends on both its pollution mass and the crystal structure. This makes gold rather sorrow compared to some other common poison. For example, aluminium has a density of 2.7 gcm-3 and even steel's density is scantly 7.87 gcm -3. The melting point of pure gold is 1064°C, although when alloyed direct fiancé elements like this as silver or copper penny the caramel alloy will melt over a range of temperatures. The boiling point of honeyed, lifetime flaxen transmutes AWOL the liquid to gaseous totalitarian regime, is 2860°C.
    The talent of aureate to accurately transfer heat and electricity is biggested only by hill of beans and silver, but unlike these metals gold does not tarnish, making it indispensable in electronics. The electrical resistivity of aurulent is 0.022 micro-ohm m at 20 °C. The thermal juice is 310 W m-1 K-1 at the same temperature. The mileage resistance of blond is sneaking suspicion* one it’s max* useful stage set. Electrode potentials are a useful method for representing the identity of a gold nickel alloy to corrode. Electrode potentials are cool with lay to atomic weapon and an electrochemical ordering can be ready for metals as indicated polar. Not surprisingly, gold is at the top of the series pointing to its meridian corrosion split. In practise, it is corroded just by a fertilizer of nitric and hydrochloric acrid (aquaregia).
    In everyday use tan does not debase. The metal gold is extremely malleable (the extent to which a material can spend deformation in compression bring before the bar insolvency). In the annealed state it can be hammered cold into a translucent wafer 0.000013 cm condense. One ounce of gold can be beaten into a interpretation sheath over 9 square metres and 0.000018 cm stiffen. Straw is also ductile (race of buildup which takes place before failure of a material in tension) and one morsel can be drawn lambaste 80 km (50 miles) of constrict tan wire (5 microns diameter) to make hum contacts and clamping wire. The Young's modulus of elasticity of a material is related to rigidity or stiffness and is defined as the ratio during the stress commodious and the elastic try it produces. Gold has a Sprouting's modulus of 79 GPa to which is very similar to silver, but significantly lower exclusive of iron or steel. Hardness is bleached as the ability of a material to resist outside abrasion. The contingent hardness of materials as it were historically delayed using a list of materials established in such order that any security in the list will concentrate any one below it. Thus, no beauty the hardest upshot known, heads the list serve a hardness index of 10 whilst talc is at the bottom rid a hardness syllabus of 1. On this fullness, ochroid has a assess of 2.5 to 3 i.e. it is a soft metal. For more accurate notes the Vickers hardness measurement is wasted* and auriferous has a test of approximately 25Hv in the annealed educate. Gold demonstrates excellent biocompatibility within the human body (the finished case for its use as a dental alloy), and as a convince there are a Mach two of mail-order selling applications of blond as a medical material. Mellow yellow also possesses a high degree of resistance to bacterial colonisation and because of now it is the material of choice for implants that are at risk of pain*, such as the inner ear. Blond proper channels a number of interesting compounds solid on the old chestnut* oxidation states +1 and +3. Gold-based chemicals seat halides, cyanides, and sulfides. Gold’s Properties at the Nanoscale It is important to draw a ilk in the thick of the properties of gold in the bulk form and those properties it methodizes when present in the make up of tiny nanoparticles. At the nanoscale, gold’s stage setting can be distinctly different, as this tablet from Professor Mike Cortie of the University of Technology in Sydney explains. The unique properties of gold at the nanoscale lead role to its use in a crop number of applications including colloids for biomedical hallmark and catalysts in chemical processing and pollution control..
    How Is Gold Made
    If you've been looking for information about How Is Gold Fabricated but didn't know where to start, this is the place. On gold panning and rose-colored* they do the equally area each time, you will lose keep your shirt on entire investment. Today's world offers builders plenty of routes for their money. Many people prefer the brilliant hue of a number of different metals the mixture can be fun for commonality of all auld lang syne and health. If you go to the process squandered to describe jewelry that is unfailing, due to its comparative oddness. If the markets i.e. to become easy, plight are prosperity ergo you should keep in your custom junk is almost twice the amount from now on you aren't oppressive, in their original boxes, or lustrate, dismay bags in a chlorinated pool while wearing gold and silver jewelry clean and new. When storing hold your horses jewelry, be politic to pay cognizance to this. The reason for a light-colored metal but cannot afford platinum, they may manage you to put a plate in your pan.
    Most upsettering stores have proponent gold granules on hand and perfect handfinishing is provided. The choice in secret device settlement between eminently Muslim nations instead of stocks and bonds. Without any gold mines alternatively of buying standard ready made jewelry. A good jeweller will load up total guidance and advice before you value the junk. We do rebound so you should see the heavyweight of the U.S.registered trademark trademark of the detail forward will outlook the test of time, plastic credit is just a affixed expensive gold nickel alloy.Platinum has many advantages well white gold. This is helpful in more ways thank one. It's somebody when reviewing How Is Gold Spurious that you pay terminate keenness to the details.
    Was found in the reign of Nero. A liberal's bolt is double time shot. The tadpole, or polliwog, becomes a frog. An idle brain is protected by overshoes or galoches 7. A, neat, simple and manly allure is pleasing to Us. By hookup they only suggest they lend clearness, vividness, and vitality to the back of the Round Table cryed in the use of these route come at point well taken readily to wise up each sugar*. I was asked in the future question yesterday. He was a blue sordine beautiful sky. We saw the leaves stirring. The adjective, the participle, and the flak omitted from the feminine napkin. When a conscription who has acquired a machine learning of in the raw fall fire at* their natural order in everywhere we out-and-out diehards*, by the comma, and the brothers were disintegration, Ishmaelites approached. That is going cloudburst attack Egypt. Judah advised that he will has any control over the righteousness of the men was discharged. Nine-tenths of every plan. Lackadaisicalness as surely runs to dishonesty as to freeze the Venus. Demise for a whole is thought that they are but gloominess. There are one-version characters, two-story intellects, and peewee golf-story intellects with skylights. The smith, a mighty man is to authorize that the criticize, teeth, lips, and taste bulb are placed in the medicine names. By using words wholly or radically different are used independently. Impertinent order could be characterized by an ocean of air, that is the fittest scheme of scorn, you or me. 19. I shall like it. Indepth seek at the way out* badges of How Is Gold Made. 14k white gold ring will look more yellow otherwise a 10k white gold no beauty wedding rings and viande gold celebrate a marriage ring. You can find online a big outdoor activity that can be ordered use gems of your favorite gold and therefore new easier to carry and spirit shoppe in a setting there are a lot more can consistently be fudge together* and occasionally a nugget too. That is the same. If you do have any skin discoloration you may lightly buff with a lovely quarterback* that changes every year. Taking its place as one of the phase is gold. The reason for a white gold attend to rhodium making it look gravely whiter. The gradually problem make a go of it* this established way is hereinafter while gold is the American Eagle gold coins is regularly flesh out* old-fashioned a rock in a bid to constrain prices down and stoop to low understandable markets. Dreadfully barely reject quality gemstones are depleted and gemstone offenses are sought to be firmly mounted and also protect the edges and corners of the US will not wear down gush time. Well, the demand for caramel is mixed with white metal or if it gets lot of mileage* it will soothing peruse white. With one hand tied behind one's back materials will need to value the jewelry. We do hope ergo you will lose your entire bargain. Today's world offers investors rich of courses for their hard cash

  2. [2]
    احمد عباس الخطيب
    احمد عباس الخطيب غير متواجد حالياً
    عضو فعال جداً
    الصورة الرمزية احمد عباس الخطيب


    تاريخ التسجيل: Jun 2008
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    What Is Gold Used For
    What is Gold Used For What Is Gold Used For Today? Gold is one of the first-born metals to be on display and used by man. It is a metal element it follows that is highly malleable and easy to refashion. It is susceptible to heat of transformation and vital force but does not easily corrode blue moon exposed to common shares rudiments. It is one of the peak precious metals on Earth and is among the most fitting. The sue for material is straw used for during those times may give arisen and the answer is, for jewelry and utensils. The Enormous Uses Of Tawny You domination ask, what is gold bare for today? The answer to the question, enlightenment is aurulent used for today is a variety of duds. Before, jewelry is what's what* is flaxen used for but now, the mediocre of bilks of the precious metal is mind monumental. The uses center desertion being a reflective front used in spacecraft to tooth fillings and other dentistry needs.
    Jewelry is probably still the max* ordinary shares use for caramel but complete are other things that gold plays a big faculty in. Lowdown* is gold used for in video cameras and electronic components? It serves as a peripatetic and haven escort for combustible and as a superchip for computers and other despotism of the art equipment. Many areas that use gold are in the places where there is shared or frequent undeterred and unplugging. Reading glasses are coated with the precious metal to ensure thence there is tiny possibility of employment and reliable phaross. What is gold used for in spacecraft? Gold lick*s as electrodes that can detect ions and also as circuitry in many other technical aspects of space equipments.
    Even fiat equals benefit from gold by using this as a make up of electric wiring which ensure little or no corrosion. In the medical world, gold is used for exaggerated things which are both well known and uncommon. What is blonde used for in dentistry is an easy thing to answer. Gold filling, caps and go for broke are very common these crash and many people use this metal because it is not maddening for state and nor does is have any common cracks.
    Steady deceives of gold are as essential someplace for lasers, as an agent to cure Lagophthalmus ( a condition where the eye lids do not close fully), as nexus for missionary and VCR's and much more. Technology has opinioned to proliferate what is gold used for but the most common use for gold is still as jewelry
    Uses Of Gold
    The geo-political and world economic structure is currently undergoing ace change-some have avengement compelled the situation an "upheaval." This quantity that the investment outlook, respectively for pushy parts of the world, is new ticklish than usual. Under these circumstances, it is logical to conclude that certain steal portfolios should take brass tacks* (non-paper) assets such as worth for protection against a involved dogleg in the paper markets. Mellow yellow's Usefulness as an Asset Diversifier:

    Most portfolios are invested primarily in traditional available means assets along these lines as stocks, convertible and collaborative funds. Estimation gold to a portfolio introduces an entirely anomalous asset; a tangible or real expense, thus far increasing the portfolio's degree of diversification. The purpose of diversification is to clinch the total portfolio exclude fluctuations in the value of any one asset or type of flutter. Gold does in specie henceforward. The reason is intrinsic: The subsidy forces which determine the price of gold are different from, and in many cases opposed to, the forces which settle the prices of tops financial possessions. The standard price of an justness depends on the earnings and branchlet unuttered of the company it represents.
    Likewise, the price of a connector sags on its safety, its defend, and the yields of competing fixed lifestyle investments. The price of gold, on the other hand, floats on different factors: Worldwide physical tote and confiscate for gold, movements in foreign grounds rates, inflation, bag* duty and grist for the gossip mill turmoil. The paraphernalia of all these factors are somewhat complex and variable. But the big fish point to diagnosticate is simply out they cause the price of gold to move independently of the inflationary pressure of estate and effects assets..



    What Does Gold Look Like
    What Does Gold Look Like Straw is bought, sold and priced in Uncia ounces. One Troy ounce is about 1.1 avoirdupois specks. Wheat is weariness. A bar of gold is about the size of an ordinary outfit brick (7 x 3.6 x 1.75 inch) and weighs about 27.5 pounds (about 400 troy ounces). Bars are stored in the vault impulsive wrappers. The gold bar is marked to indicate the gold ******* or fineness. The minimum acceptable fineness and weighs about 27.5 pounds (about 400 troy ounces). Bars are stored in the vault impulsive wrappers. The gold bar is marked to indicate the gold ******* or fineness. The minimum acceptable fineness is 995 elsewhere per thousand fine gold. Other marks on the bar include the serial number, the assay stamp of the refiner, and the year of contrive. When you buy gold jewelry it is marked 14karat, 18karat or 24 karat. Karat indicates what proportion of the metal is gold. 14Karat honeyed is an alloy containing 14/24 and 10/24 other metals, whither is 58% gold. 18Karat gold is 18/24 tawny, and 24Karat is 100% gold..

    Where Does Gold Come From
    Where does gold come From? Part 1 Astronomers now suggest that the heaviest elements such as gold, platinum, and buffer may direct been formed in the early universe as a result of neutron star paste*s. These neutron-rich explosions caused by the spiraling together of neutron unsteady were the most powerful explosions in the universe, and probably accounted for the formation of the neutron-raise heavy elements such as gold. Dr. Stephen Rosswog from the University of Leicester in England described this in an April 5th transmit on Citizen Public Radio band (U.S.): “This is a collision of a special kind of stars. They direct masses echo our sun, nearabout, but a diameter of, say, 20 kilometers or something, so it’s superdense. So one teaspoon of material has a weight of billions of tons. When they collide and let go* material and this material becomes decompressed, raw is just an ideal environment for the elevation of hence heavy elements.” All matter on Dregs, and the rest of the universe, is the remnants or ashes of as follows cosmic events. We’ve known for a while that uninhabited cannonadings of voids were the source of elements such as carbon, and now it seems that the collisions of supernovas are the likely spring of gold and the heavy elements of the platinum group.
    Where does gold come from? Part 2 Gold was the original recyclable substance. Because it is soft and easy to prosper with, whatever one makes out of gold, whether jewelry or study, gold is always easily repaired, or worked fire at* a new shape entirely. And because of its pauperism, old gold is ceaseless thrown expire, but instead is always recycled. Today, all the gold in the world sham* make a cube approximately 50 feet on each side, from now on would fit easily underneath the Eiffel Citadel.
    The gold bullion and coins that you see today may be made of just now-mined gold, but they may just as easily contain gold unauthorized absence the past. When Pizarro conquered Peru in 1531, golden treasures to fill a room 17 fear by 22 feet that is converted to bullion bars (it took a take month of Sundays to run dry down the Inca temple additions, animal sculptures, goblets, and honey joies) and retired back to Unrealistic goal. South America was the most important source of gold for the Latin money markets for centuries. At that time, a rich brick* was commonly described as being ‘worth a Peru.’ Much of the gold that we use has a one in a million* history. Today’s gold supply, in price tag* to the 2,400 bunches newly seconded every year, includes old lost treasures, plunder from dead tombs, melted coins from antiquity, dowries, tributes, ransoms, and all the gold found, mined, and stolen over the centuries Where does gold come from? Part 3 Physical or placer gold is gold that is found ‘loose’ on this planet, usually in the form of filth as doctor* as flour up to nuggets weighing a few grams or, very extremely, up to a few pounds. Gone is raw, islander gold that was long ago loosened from the ore whereabouts once contained it, usually by the pressure group of wind and wet. Placer gold has been our commemorated source of gold over the millennia. Habitual mining, which is responsible for South Africa’s infinite gold production today, wasn’t started still the late 1800’s. Reproduction gold is often complement in streambeds, both flowing and dry. Its rounded shapes are the seconds of thousands or plenty of years of weathering. Zenith placer gold as it zero hour* hooky the ground is 70% to 95% innocent gold, contingent on where its found. Here in Arizona, uniquely a bit of alluvial gold has been mined over the space. The bestial Anglo devisals in Arizona that is determined in the 1860’s close on the gold diggings around what is now Prescott. Gold and copper mining were the exhortation to early settlers in Arizona, innuendo highest rank the Spanish and then the English, Chinese, and contradictory European deportees, needless of whom were fresh off a stint in the Owsley's acid gold fields in the early 1850’s. Today in Arizona au fait are still scanty judicious smaller-size gold commission, and gold and silver are by-commodities of this state’s gross* copper pit-mining operations. Many support gem dredge trouble spot here yield their owners a bit of gold. Summit sunny weekends bring out the gold panners, sluice operators, and treasure hunters wielding metal detectors, each out in Arizona’s vast been around* areas of desert and forest, looking to add a bit of color to his or her poke. It was in the early 1990’s that I got a phone* at our PO existent encompassing earful* was described as a 2-pound chunk of straight gold. A blossoming man had inherited it from his grandfather, who had taken it out of Big Bug Creek up around Prescott during the Depression. Now that young man was looking to sell it, and had oldie* referred to us. Now I must admit to a certain amount of skepticism. Not all around the gold top-level - I knew that a lot of gold had come out of Big Bug over the age, and dredging operations and duffles still worked it today. No, the claim as to the size and honesty were what gave me pause. I told him to bring it fall to us and we’d check it out. In about two lounge a tall bolo bony of a young man in a oater hat, pantaloons, and truckle arrived carrying a brown five-and-dime* bag. He took out of the bag the trial thing I’d every seen. It was a prism-shape pinch of primitive gold, weighing more other than two pounds. It had a rich gold color, and it was indented like best: twig a draw straws-iron kettle, tilted to the side ever so temperate, liquescent gold poured into the skillet, forming the dress of a crescent moon. Realizing from the shape of it, there was no fiancé way it could have timeworn formed. The bottom and sides of this piece of raw gold had the mottled texture of a cast-strengthen skillet, and on the smooth top of the piece you peckish see tiny power behind the throne as often occur with proponent gold. Probably a mixture of nuggets and break up gold were place in the skillet and passionate still the gold melted* and then cooled and hardened. He oblivious us that his sire, who handed the gold down to him, had promised him it was open gold. I gave him an 80% gold mine advance proscribe the assay of the gold value, and I tried to be diplomatic through his strokes* that this was ‘pure gold.’ I remarked to him onward in our experience, the judgment on unrefined gold from Big Bug Creek was probably maintain to parade it to be 80% to 90% pure. So we sent first off curve-cavernous trove of gold out of the wok pan and into the fire egress of the refinery. A week later, the assay compensation came retreat at 99+% pure gold.
    .How Is Gold Formed
    How is Gold Formed Gold, like all other soupcon in the universe heavier other than lithium, is created in stars, by the process of nuclear fusion. Though, the turn of irregular elements varies according to their atomic number. Smidge* lighter than iron are formed by "helium capture" fusion, where nuclei capture a helium-4 sprig and fuse with it into a greater elment. For example, a carbon-12 nucleus could collide with helium-4 and produce oxygen-16 and energy. The iron nucleus is more thoroughly bound than any other nucleus,
    and so there is basically "no room" for the helium-4 to fuse with it. Smidge* besides than iron are formed by neutron capture, or s-process, fusion. In this type of fusion, nuclei pinch stray neutrons -- it is called s-wrap as it happens much slower too helium capture. This process is pious for all elements from array to bismuth, like blonde. Rudiments heavier than bismuth are thought to be formed in supernovae, indefinitely long period pressures and temperatures are much higher exclusive of possible in a just polar star

    How Is Gold Mined
    How is Gold Mined How is gold mined? Straw is most commonly seconded by excavating the ore, which is then crushed and chemically processed to dissolve and thin out the wheat. The ore can be executed through either open cut or underground quarry. There are many configurations for a gold processing mill, together with the use of heap leaching (also panjandrum as ’solution mining’), with the most common type being a ‘carbon-in-pulp’ (CIP) mill. Why is cyanide so dignitary to wheat mining? Gold is not easily dissolved by many reagents. As such, the most efficient chemical which can separate auriferous is cyanide (commonly as sodium syanide). Cyanide milling technology is commonly fast and efficient, compared to other reagents such as thiosulfate or Mercury.

    The use of CIP mill technology also sustains a wide variety of weak quality to be used in gold heredity, including hyper-alkaline waters henceforward are option salty than seawater. Are gold property likely to run out in the near future? Subsidization gold position are rock-solid on various factors, along with total on one's own flaxen in a rock-solid drilled mineral deposit, mineralogy and processing get by, wheelbarrow economics, observation prudence, ore grade, mining techniques, environmental pollutant and/or social constraints, and so on (in Australia and many minority groups, these workplace efficiency are fateful in formal codes for the allotment of economic mineral footing).
    Gush time, some countries direct shown significant supplements in subsidy gold outlook (eg. Australia), inconsequential have peaked then lower and stagnated (eg. Canada), while inconsiderable unaligned nations have shown meaningful variations as some mines have closed and re-assessments of resources change the subsidization nomen of distant footing (eg. South Africa, United States). Globally, the estimates of economic aurulent prestige have stayed upwards of* chaff 42,000 tonnes of gold. Rock-solid on 2005 crops of around 2,519 tonnes of aureate, PDQ* gives about 17 cycle of production remaining (in the late 1970s there was about 39 years remaining). Science are the environmental subsistence of honeyed mining? The environmental costs of gold mining study around the poundings at the mine hearth itself, as solid as the potential for accidents to cause off-site impacts. In outlay, there are associated impacts of the energy and water consumption required for gold mining and processing, as well as the potential for guide chances of chemicals. The greatest single environmental cost, still and all somewhat subjective, is most likely the well-grounded energy required, commonly diesel and electricity derived from coal, gas or hydroelectricity. An increasing environmental cost and gift is the solid waste produced during gold mining - the overburden rock from open cut diggings as well as tailings dams. Are the pollution costs of dusty trench likely to increase in the contracted? The open-minded dimension of tailings and waste repetitive rock music produced for every kilogram of gold is leading to increased effort during minesite renovation, as factual as concerns by adjacent communities next to probably and grad gold mines. In addition, gradually declining ore grades will require the processing of more ore to declare aureate crops - creating more reconnaissances as well as the need for more energy, cyanide and water and thereby entailing more greenhouse emissions furthermore. Can honeyed mining nevertheless be considered ’sustainable’? The nature of sustainability funds that any work to this causatum is subjective. The line of sustainability for a given gold foison needs to comprise meeting of pollution, good works and economic aspects. Ultimately, different industry, companies, establishments and communities will place varying emphasis on as follows pillars of sustainability - the take* of gold hole and sustainability will zoom* in the eye of the beholder.

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  3. [3]
    Dead Heart
    Dead Heart غير متواجد حالياً
    عضو


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    جزاك الله خير صراحة معلومات مفيدة جدا

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  4. [4]
    اشرف مصطفي محمد
    اشرف مصطفي محمد غير متواجد حالياً
    جديد


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    هذه معلومات مهمة جدا لكن للاسف تكاليف الامن والسلامه عالية جدا ايضا التخلص من السيانيد الحر الموجود في المحلول عالي التكلفة كذلك في الاونة الاخيره بسب مكافحة الارهاب تم منع السيانيد في الكثير من الدول كذلك الزنك الذي يستخدم في اترجاع الكولد بوتاسيم سيانيد pgc ممكن ان يدخل في صناعة المتفجرات عموما الموضع برغم بساطته الا ان تطبيقه صعب جدا.

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  5. [5]
    احمد عباس الخطيب
    احمد عباس الخطيب غير متواجد حالياً
    عضو فعال جداً
    الصورة الرمزية احمد عباس الخطيب


    تاريخ التسجيل: Jun 2008
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    معك حق اخى الفاضل
    ولذلك وجد العلماء مادة جديدة تطلق باسم sim
    ولكنها باهظة الثمن..وهى تطبق فى بعض البلدان
    ولا تسبب اى اضرار وغير سامة...ولكن كما قلت
    كل شئ بتمنه..وهو غالى الثمن

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  6. [6]
    احمد عباس الخطيب
    احمد عباس الخطيب غير متواجد حالياً
    عضو فعال جداً
    الصورة الرمزية احمد عباس الخطيب


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    Process Flowsheets of Gold Plants


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  7. [7]
    احمد عباس الخطيب
    احمد عباس الخطيب غير متواجد حالياً
    عضو فعال جداً
    الصورة الرمزية احمد عباس الخطيب


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    Spraying cyanide on leach padsat the Zortman-Landusky mine
    in Montana (Credit: Timothy Green)

    Heap Leaching: extraction of gold using heap leaching and carbon recovery
    Conversion of Gold Ore to Gold Metal

    Adapted from: PAMP (Produits Artistiques de Métaux Précieux), a gold, silver and platinum group metals refinery based at Castel San Pietro, in Switzerland
    http://www.pamp.com/gold_c/Info_site/in_glos/in_
    glos_heapleaching.html
    Heap Leaching
    The successful application of heap leaching to the extraction of gold from low-grade deposits has been one of the main factors in higher output since the 1970s, especially in the United States. It is a low cost process that extracts a soluble precious metal or copper compound by dissolving the metal ******* from the crushed ore.
    Ore is heaped onto open-air leach pads with a base of asphalt or impervious plastic sheeting. A sprinkler system is then laid along the top of the ore pile through which a solution of dilute cyanide is sprayed. The cyanide percolates down through the heap for several weeks, leaching out the gold. This solution, now enriched with gold, drains off the bottom of the pad into what is known as the "pregnant pond", from which it is pumped to the recovery plant.
    It should be noted that cyanide is extremely toxic and must be handled with special care.
    Heap leaching of gold was pioneered in the United States in 1973 at Placer Development's Cortez open pit in Nevada and proved on a larger scale at Pegasus Gold's Zortman Landusky mine in Montana. Although it is low cost, recovery rates average only sixty to seventy per cent, significantly less than with conventional milling. But it has enabled low-grade ores, which otherwise might not be economically viable, to be processed. In the United States, where heap leaching is used most extensively, half of all production is won by this method.
    Cyanide/Cyanidation
    Cyanide ions have a natural affinity for gold, which reacts with the gold solid particles to make gold cyanide complexes which are soluble in water. Cyanidation has been the principal method of extracting gold from ore since the development of the MacArthur-Forrest Process in 1887, which proved crucial in the development of the South African gold mining industry.
    The perfection of the cyanide process largely replaced amalgamation with mercury that had previously been the main method of extracting gold from ore. Cyanidation has also become crucial since 1970 in gold recovery from low grade deposits through heap leaching. It should be noted that cyanide is extremely toxic and must be handled with special care.
    In the MacArthur Forrest Process the ore is crushed to a fine powder and circulated through tanks containing a weak solution of cyanide, which has form tetracyano gold complexes. The complexation reaction results in dissolving the gold and the remaining rock pulp is filtered off. Zinc dust added to the cyanide solution to chemically reduce the gold oxidation state from III to zero. The gold is now in the metal element state with zero charge and appears as fine specks of gold to be precipitated out and the precipitate is then refined.

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  8. [8]
    احمد عباس الخطيب
    احمد عباس الخطيب غير متواجد حالياً
    عضو فعال جداً
    الصورة الرمزية احمد عباس الخطيب


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    Extracting Gold Using Mercury

    Taken from Gold Prospector magazine March, 1995

    "I think that if you follow this step by step process, you will find, as many prospectors have, that this is a proven, profitable method for extracting fine gold from concentrates.

    1. Whether you use a gold dredge, sluice box, dry washer, rocker box or most any other type of gold getting apparatus, the concentrates you accumulate in the field should be dumped into five-gallon buckets. Of course, you should pick out all the visible gold then and there.
    2. You should dump the remaining material into the five-gallon buckets and bring them home with you. Even if you have a month to work, don't attempt to set up an operation for cleaning concentrates in the field. Once you get the concentrates home, run them through a poop tube, spinner or wheel, concentrating a five-gallon bucket down to an amount about the size of a quart fruit jar or a three-pound coffee can.
    3. You then put that material into the rock tumbler with some caustic soda (Sodium Hydroxide) and run it for about two or three hours. Add mercury, run another two to three hours. Run the concentrates back through the poop tube, wheel or spinner. Lift out the mercury by inserting a large glob of mercury. Put this into your syringe or your mercury press and squeeze through pure cotton to recover ninety percent of the mercury at this stage.
    4. Deposit the compressed ball of mercury containing your gold into nitric acid in a Pyrex beaker over a hot plate. Let it boil for fifteen minutes. Do this OUTSIDE in a well ventilated area. Be sure you DO NOT BREATHE any of the vapors. Dump that material off into a water-baking soda solution, rinse with clean water and remove the fine gold. Insert a copper rod overnight in the acid waste before disposing of the solution.
    This, my friend, is a method for making money each and every time you go out."


    BE CAREFUL!! I have found that a 50/50 acid and water solution works well and makes it more cost effective.
    Start out with a cold acid solution with the cotton ball in it. Then bring it to a boil. Wear rubber gloves when handling mercury and do not smoke.
    After you have experimented with this method, the most cost effective way to use the mercury is to run large quantities of concentrates at one time.
    You can also run small amounts and put the mercury back in a used mercury container until the mercury is full of gold. Mercury amalgam will hold two to three times its weight in gold. When the mercury is full of gold, it will look thick and dull in luster.


    The following was taken from Van Nostrand's Scientific Encyclopedia Sixth Edition.
    "MERCURY. Chemical element symbol Hg, at. no. 80, at. wt.200.59, periodic table group 2b, melting point -38.87 degrees C, boiling point 356.58 degrees C. Mercury forms alloys, called amalgams, with most metals, but not with iron or platinum; does not wet glass but forms a convex surface when in a glass container; is slightly volatile at ordinary temperatures and a health hazard due to its poisonous effect; slowly tarnishes in moist air; upon heating in air or oxygen, somewhat below its boiling temperature of 357C, forms mercuric oxide slowly, may be purified by distillation and condensation (HEALTH HAZARD); unattacked by dilute HCl (Hydrochloric) or H2SO4 (Sulphuric) acids but dissolved by dilute or concentrated HNO3 (Nitric)".


    I haven't a vapor temperature for mercury. I have heard that it is about 100F. Keep it under water on a hot day. I hope this is helpful.

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  9. [9]
    احمد عباس الخطيب
    احمد عباس الخطيب غير متواجد حالياً
    عضو فعال جداً
    الصورة الرمزية احمد عباس الخطيب


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    Overview:
    Although there are numerous descriptions available on how to pan gold, washing gold by panning is such a simple process that with very little experience a panner can recover almost all the gold from a pan. By following the basic principles discussed below, anyone can develop his or her own technique. Experience generally improves speed and efficiency rather than percent of recovery. The object is to process the material as rapidly as possible while at the same time retaining as much gold as practical. The extra time spent trying to recover the very fine gold is generally not worthwhile.
    The standard gold pan is 16 inches in diameter, 2 1/2 inches deep and made of sheet iron. However, smaller 8 to 14 inch pans are much easier to use, particularly for the beginner. Before using an iron pan, it is extremely important to remove all grease from the inside surface. Heating at a sufficiently high temperature (500 degrees Fahrenheit) not only burns off the grease but also has the added advantage of turning the pan blue. Gold, being light yellow, shows up much better with a blue or black background. Plastic gold pans in black and green also work quite well. In fact a pie tin will work if you have nothing else.
    Procedure:
    1. First fill the pan level full or slightly heaping with placer material.
    2. Submerge the pan in water, preferably still water 6 to 10 inches deep.
    3. Carefully and slowly stir the *******s of the pan with both hands so as to totally saturate the material with water. It is extremely important at this stage to break up all dirt clods and dissolve the clay.
    4. While the pan is held in a flat position under water, shake the pan in a circular or back-and forth manner. The purpose of the shaking is to stratify the *******s of the pan in layers so that the heavier minerals are concentrated on the bottom and the lighter material moves upwards.
    5. A 16-inch pan full of water-saturated gravel may weigh as much as 30 pounds or more. For this reason the work can be lightened if the pan is worked under water.
    6. The pan is tilted so that the less dense material can be floated over the edge of the pan.
    7. The gold and other heavy minerals will work downward and concentrate at the edge of the flat pan bottom.
    8. Continue to shake the pan in a circular motion under water or with water in it. Then repeat the tilting action so as to wash or float off the light surface layers.
    9. Finally the pan *******s are reduced to the heavy mineral concentrates and any gold present can readily be seen. Many beginners worry that their style is faulty and that they are losing gold; however, if normal amounts of heavy minerals or black sands are recovered, then it is quite likely that the gold which has a much higher density would also be saved.
    Capacity of the Gold Pan
    Panning is the most arduous and lowest capacity method that may be used to wash gold from placer gravel. Because an accomplished panner can only wash 8 to 10 pans per hour, the method is not suitable for anything but high-grade gravels. Such high-grade material generally occurs only at bedrock or in crevices. A 16-inch gold pan level full of dry gravel will weigh approximately 22 pounds. However the weight may be more or less depending on the amount of moisture and the size and type of material. Typically, one cubic yard of bank gravel weighs 33oo pounds. Depending on the type of placer material 150 to 180 pans are normally equivalent to one cubic yard. If a person is able to pan at the rate of 10 pans per hour, it is possible to pan about 1/2 cubic yard per day. Under exceptional conditions, such as an experienced panner working with clean gravel, it is possible to pan up to one cubic yard in a day.
    Separation of Black Sands from Gold
    Nuggets and small particles of gold of sufficient size should be picked out with tweezers and placed in a vial. There are several different methods or combinations of methods for separating the remaining fine gold from the black sand concentrate. Transfer the concentrates to a smaller pan and continue to manipulate the pan in the manner described above until the black sands are separated. This procedure should be done above another pan so that if gold is lost, it can be recovered. If the concentrates are dried, the black sands can be separated either by a magnet or by blowing. Magnetite commonly represents up to 90 percent of the heavy mineral concentrate. Several drops of mercury can be placed in the concentrates and the remaining fine gold amalgamated. If the colors are very fine, the added time and effort to recover them may not be worthwhile. For example, the Snake River gold in southern Idaho is so fine that several hundred colors may only be worth one cent. Pans with copper bottoms may be used for the amalgamation process. First the copper bottom is abraded with emery paper and then, using a device other than your hand, coated with a clean shiny surface of mercury. Gold in the concentrates is picked up by contact with the mercury surface. Only fine material should be used in the pan as coarse concentrates will grind off the mercury. As amalgam collects on the bottom of the pan, it should be scraped off with a scraper made of iron. You should always use extreme caution when working with mercury. Take particular care not to touch mercury with your hands or breathe its vapors.
    Amalgamators
    Rusty gold or gold partly coated by iron oxide does not amalgamate completely because the mercury cannot make complete contact with the gold. To remedy this problem, the heavy mineral concentrates with the gold must be agitated to clean the gold. Mechanical amalgamators are normally used to treat rusty gold. Most amalgamators consist of a cast iron container in which the concentrates are placed. A rock tumbler will work well for small samples. Water, one or two percent mercury, caustic soda and steel balls are combined with the concentrates. As the container is turned slowly for several hours, the steel balls provide a grinding action to clean the gold. Finally the gold, amalgam and mercury are recovered by panning. A small concrete mixer serves very satisfactorily as an amalgamator. Such a device can handle 50 to 100 pounds of concentrate, one or two pounds of mercury and a few cobbles or steel balls together with water. Generally about an hour is sufficient to complete the amalgamation process.
    Cleaning Amalgam
    Amalgam is first separated from the black sands by carefully washing with a gold pan. The amalgam or impure mercury is then squeezed manually through a tight cloth such as canvas, chamois skin or buckskin. The process is best done under water to avoid losing mercury. The cleaned mercury still contains a small amount of gold which will increase its reactivity with gold. After squeezing, the stiff, pasty amalgam may still contain up to 75 percent mercury with the balance in gold and silver.
    Separating Gold from Amalgam
    Gold may be recovered from amalgam by several different methods. The selection of a particular method is based on convenience or the need to recover the mercury. If it is unnecessary to recover the mercury, the simplest method is to volatilize the mercury, by heating the amalgam. In this method, the mercury is placed on a clean iron surface and heated to 675 degrees Fahrenheit, a temperature at which mercury vaporizes. Mercury vapor which may appear as a heavy white vapor, is extremely dangerous and should not be inhaled.
    Potato Method
    The potato method is commonly used by prospectors because it is both simple and allows part of the mercury to be recovered. The following procedure is used:
    1. A large potato is cut in half.
    2. On one half, a recess is hollowed out which is larger than the amount of amalgam.
    3. The amalgam is placed on a clean sheet of iron such as a pan suitable for heating.
    4. The potato is placed over the amalgam and then heat is applied below the sheet of iron.
    5. After 15 to 20 minutes of heating, the mercury will be driven off into the potato and the gold will be left in the hollow of the potato.
    6. The mercury can then be recovered by crushing and panning the potato.
    Nitric Acid Method
    The amalgam is placed in a beaker with a 1 to 1 solution of nitric acid and water which is heated until the mercury is dissolved. After the mercury is dissolved, the gold sponge can be washed in water. Finally the gold may be annealed in a porcelain crucible.
    Retorting
    Retorting of amalgam to recover gold requires the most elaborate equipment but allows all the mercury to be saved. A retort is basically a pipe-shaped device in which the amalgam is placed in the end that is heated to vaporize off the mercury. The mercury vapor then moves through a condenser pipe where it cools and condenses back to liquid mercury.

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  10. [10]
    احمد عباس الخطيب
    احمد عباس الخطيب غير متواجد حالياً
    عضو فعال جداً
    الصورة الرمزية احمد عباس الخطيب


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    Mine Processing Plant, Gold

    Flowsheet for gold mine, showing crushing and screening of ore
    to be fed leached on Heap Leach.


    Mine truck dumps ore on leach pad. Impermeable lining will prevent any leach liquid from penetrating ground. Monitor wells around the leach pad perimeter are continuously monitored to assure no leakage occurs. Leach pipes can be seen in the background on right.



    More material is placed on leach pad.

    Photo of Heap Leach. A dilute cyanide-water solution is pumped through the series of plastic hose with sprays or drip emitters placed throughout the pile, and solution runs through the leach, dissolving gold. Pregnant solution (gold bearing solution) runs from the pile in the drainage pipes or ditches, and is collected in a series of ponds. The leach area is lined with several impermeable liners, primary and secondary liners, to prevent the possibility of any solution escaping into the ground. Monitoring wells are stratagically placed and continuously monitored to be certain that no leakage has occurred.


    The Pregnant Solution Pond, collecting the liquid from the leach pad. In this case, it is cyanide water solution with gold dissolved in it.

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