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My Note Page |
"My Note Page" is an unique collections of useful information
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:: All About Gold :: |
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(1) Facts About Gold - (Nothing works like Gold) |
Reference Source : http://goldinstitute.org/facts/
Accessed on : Saturday, August 30, 2003 |
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(A) PROPERTIES OF GOLD |
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Out of the earth comes a remarkable metal with an unparalleled combination of chemical and physical properties that make this metal invaluable to a wide range of everyday applications essential to our modern life. Thousands of common, everyday appliances require gold to ensure perfect performance over a long period of time. This indestructible metal is completely recyclable and virtually immune to the effects of air, water, and oxygen. Gold will not tarnish, rust, or corrode. This unique combination of properties makes gold a vital component in many medical, industrial, and electrical applications. These properties include: |
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(a) RESISTANCE TO CORROSION |
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Gold is the most non-reactive of all metals. It is benign in all natural and industrial environments. Gold never reacts with oxygen (one of the most active elements), which means it will not rust or tarnish. The gold death-mask in the tomb of Tutankhamun looked as brilliant when it was unearthed in 1922 as when it was entombed in 1352 BC. |
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(b) ELECTRICAL CONDUCTIVITY |
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Gold is among the most electrically conductive of all metals. Since electricity is essentially the flow of charged particles in a current, metals that are conductive allow this current to flow unimpeded. Gold is able to convey even a tiny electrical current in temperatures varying from -55° to +200° centigrade. This makes gold a vital component for electrical connectors in computers and telecommunications equipment. |
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(c) DUCTILITY AND MALLEABILITY |
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Gold is the most ductile of all metals, allowing it to be drawn out into tiny wires or threads without breaking. As a result, a single ounce of gold can be drawn into a wire five miles long. Gold's malleability is also unparalleled. It can be shaped or extended into extraordinarily thin sheets. For example, one ounce of gold can be hammered into a 100 square-foot sheet. |
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(d) INFRARED (HEAT) REFLECTIVITY |
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Gold is the most reflective and least absorptive material of infrared (or heat) energy. High purity gold reflects up to 99% of infrared rays. This makes gold ideal for heat and radiation reflection, as in life-saving face shields for astronauts and firefighters. |
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(e) THERMAL CONDUCTIVITY |
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Gold is also an excellent conductor of thermal energy or heat. Since many electronic processes create heat, gold is necessary to transfer heat away from delicate instruments. For example, a 35% gold alloy is used in the main engine nozzle of the Space Shuttle, where temperatures can reach 3300° centigrade. Gold alloy is the most tenacious and long-performing material available for protection at these temperatures. |
