Industrial and modern uses of Gold and silver :Retrospectives and Prospectives 0
Of all the minerals mined from the Earth, none is more useful than gold. Its usefulness is derived from a diversity of special properties. Gold conducts electricity, does not tarnish, is very easy to work, can be drawn into wire, can be hammered into thin sheets, alloys with many other metals, can be melted and cast into highly detailed shapes, has a wonderful color and a brilliant luster. Gold is a memorable metal that occupies a special place in the human mind.
Historical uses of gold;
Throughout the history of our planet almost every established culture has used gold to symbolize power, beauty, purity and accomplishment. Today we continue to use gold for our most significant objects: wedding rings, Olympic medals, Oscars, Grammys, money, crucifixes and ecclesiastical art. No other substance of the same rarity holds a more visible and prominent place in our society.
Uses of gold in jewelry making:
The production of ornamental objects was probably the first use of gold over 6000 years ago. Gold is found in the pure state, is very easy to work and was probably the first metal used by humans. Today, most of the gold that is newly mined or recycled is used in the manufacture of jewelry. About 78% of the gold consumed each year is used in the manufacture of jewelry.
Measurement of purity in gold:Purity of
The properties of an attractive metal that is easily worked into beautiful objects. Another extremely important factor that demands the use of gold as a jewelry metal is tradition.
The alloys of gold have a lower value per unit of weight than pure gold. A standard of trade known as “karatage” was developed to designate the gold content of these alloys. Pure gold is known as 24 karat gold and is almost always marked with “24K”. An alloy that is 50% gold by weight is known as 12 karat gold (12/24ths) and is marked with “12K”. An alloy that contains 75% gold by weight is 18 karat (18/24 = 75%) and marked “18K”. In general, high karat jewelry is softer and more resistant to tarnish while low karat jewelry is stronger and less resistant to tarnish – especially when in contact with perspiration.
Alloying of gold with other metals:
Alloying gold with other metals changes the color of the finished products.
An alloy of 75% gold, 16% silver and 9% copper yields yellow gold. White gold is an alloy of 75% gold, 4% silver, 4% copper and 17% palladium. Other alloys yield pink, green, peach and even black colored metals.
Gold and silver as medium of exchange:
Because gold is highly valued and in very limited supply it has long been used as a medium of exchange or money. The first known use of gold in transactions dates back about 6000 years. Early transactions were done using pieces of gold or pieces of silver. The rarity, usefulness and desirability of gold make it a substance of long term value. Gold works well for this purpose because it has a high value, is durable, portable and easily divisible.
Some early printings of paper money were backed by gold held in safe keeping for every unit of money that was placed in circulation. The United States once used a “gold standard” and maintained a stockpile of gold to back every dollar in circulation. Under this gold standard, any person could present paper currency to the government and demand in exchange an equal value of gold. The gold standard was once used by many nations but it eventually became too cumbersome and is no longer used by any nation.
The gold used as a financial backing for currency was most often held in the form of gold bars, also known as “gold bullion”. The use of gold bars kept manufacturing costs to a minimum and allowed convenient handling and storage.
Gold bullion and coins:
Today many governments, individuals and institutions hold investments of gold in the convenient form of bullion. Today gold coins are no longer in wide use for financial transactions. However, gold coins issued in specific weights are popular ways for people to purchase and own small volumes of gold for investment. Gold coins are also issued as “commemorative” items. Many people enjoy these commemorative coins because they have both a collectable value and a precious metal value.
Uses of gold in electronics:
The most important industrial use of gold is in the manufacture of electronics. Solid state electronic devices use very low voltages and currents which are easily interrupted by corrosion or tarnish at the contact points. Gold is the highly efficient conductor that can carry these tiny currents and remain free of corrosion. Electronic components made with gold are highly reliable. Gold is used in connectors, switch and relay contacts, soldered joints, connecting wires and connection strips.
A small amount of gold is used in almost every sophisticated electronic device. This includes: cell phones, calculators,