Gold is the material of choice in many electronic applications, especially in telecommunications, information technology and other high performance and safety critical applications. Examine your mobile phone and you will almost certainly see gold plated contacts. Take apart an old computer and there will probably be gold plated edge connectors on the circuit boards.
As a result of the growth of these sectors, long term annual consumption of gold in electronics is increasing. During 2007, it was estimated that around 280 tonnes of gold found its way into electronics and electrical components. Where the voltages are small, the circuitry complex or the required reliability high, gold is usually the preferred choice.
The beneficial material properties of gold include outstanding resistance to corrosion, the ease with which it can be worked and high thermal and electrical conductivity. Only silver and copper are better conductors of electricity, but do not have comparable resistance to tarnishing or corrosion. In conditions under which most other metals either tarnish or corrode away, gold remains inert and extremely durable.
Gold Bonding wire is the single most important use of gold in terms of tonnage of gold used per year. Wire bonding is the method used to attach very fine gold wire (typically thinner than a human hair at 10-200microns) from one connection pad to another, completing the electrical connection in an electronic device. Literally billions of wires are bonded every year in the world and most are used in the integrated circuits (ICs) we take for granted in all manner of electronic goods.
Gold plating is a commonly used term to describe a thin gold coating on an object. Gold electroplating is used for making contacts and connectors and so is the biggest use of gold in electronics.
As well as gold based finishes on contacts and connectors and gold bonding wires in semiconductor devices, gold is used in
1. Thick and thin film gold paste applications
2. Sputtered gold metallisations
3. Gold based solder alloys
4. Solderable gold based coatings for printed circuit boards
In general, the more sophisticated the equipment and the greater the need for reliability, the greater the requirement to exploit the advantages of gold as a material. This means that in telecommunications, computers, automotive electronics and defense systems where safety is critical, gold is indispensable.
Gold’s reflectivity, conductivity and corrosion resistance have long made it a vital material in mankind’s exploration of space.
It’s efficiency as a reflector of heat and infra-red radiation has led to gold being used to in many of NASA’a undertakings. So reflective gold-coated plastic film is wrapped around parts of the equipment that are subjected to a steady stream of intense static generating solar radiation and heat. In a similar way, a layer of gold on the helmets of astronauts enable them to work in space safe from the lethal effects of this radiation. The Mars Global Surveyor had an on-board gold-coated parabolic telescope-mirror that helped to generate a detailed map of the entire Martian surface over a two-year period.
The $1.5 billion Hubble telescope has been protected by gold coatings to provide corrosion resistance and electrical connections. Nearly 41Kg of gold was used in the construction of the US Columbia space shuttle, especially in brazing alloys, fuel cell fabrication, for coated plastic films or in electrical contacts.
Uses for Gold In Medicine
A number of research groups around the world are using the unique properties of gold to develop new anti-cancer treatments. Gold drugs have long been used in the treatment of rheumatoid arthritis reducing the symptoms of pain and stiffness.
Gold possesses a high degree of resistance to bacterial colonization and because of this it is the material of choice for implants that are at risk of infection. Colloidal gold is the perfect material for use in rapid testing. A rapid test (e.g. pregnancy testing) is an inexpensive, disposable device that provides visual evidence of the presence of a substance in a liquid sample.
The advantages of gold and its alloys for dental applications are its bio-compatibility, malleability and resistance to corrosion.
The American Dental Association, the leading U.S. professional body for the profession, provides a technical evaluation of the main metals and materials used for dental restorations, including gold alloys.
Due to its unique chemical and metallurgical properties gold is has a vital role to play in future technologies aimed at reducing pollution and energy consumption. Examples include:
Diesel Emission Control
The recent announcement by U.S. company Nanostellar that they have developed an automotive pollution control catalyst for diesel engines that contains gold, as well as the traditional platinum and palladium ingredients, is a major step-forward in cost effective emission control.
The US is relying increasingly on the use of coal to produce electrical power and significant levels of mercury occur in the effluent from these power plants. Control of mercury, which has been linked to Alzheimer’s disease and autism, is expected to be achieved in the US by imposed limits on mercury emissions from coal-fired boilers in the utilities industry. One method to increase mercury removal is to introduce a catalyst to enhance the oxidation of mercury and gold catalysts are proving to be very promising.
Green chemistry, also called sustainable chemistry, is a chemical philosophy encouraging the design of industrial chemicals and processes that reduce or eliminate the use and generation of hazardous substances. The use of gold as a catalyst has a major role to play in green chemistry.
Chlorinated hydrocarbons are major pollutants of groundwater. For example, trichloroethene is used to degrease metals and electronic parts in the automotive, metals and electronic industries and also in chemicals production, textile cleaning and consumer products. Recent research at Rice University's Centre for Biological and Environmental Nanotechnology has revealed that bimetallic gold-palladium nanoparticles provide an active catalyst to break down trichlorethene (TCE), one of the most common and poisonous groundwater pollutants. TCE has been linked to liver damage, impaired pregnancy and cancer. The new catalyst works better than the carbon filters currently in use because it converts the TCE to non-toxic components instead of just trapping it in the filter. It also performs better than iron because it is not consumed in the reaction and, thus, can be used repeatedly; in contrast, iron catalysts produce toxic intermediate chemicals such as vinyl chloride.
Palladium catalysts have previously been shown to remove trichloroethene and other chlorinated compounds from water effectively at room temperature using hydrogen, but catalyst cost is a significant barrier to widespread adoption. In order to use less metal, Dr Wong’s team at Rice coated small amounts of palladium atoms onto gold nanoparticles. The increase in catalytic activity was exciting. Gold is more expensive than palladium but, since the nanoparticles are so much more active they are more cost effective. This nanomaterial opens up tremendous opportunities in groundwater clean-up. In other work, researchers from the Indian Institute of Technology, have proven that gold nanoparticles, incorporated into a point-of-use water purification device, can be effective in the capture and removal of halocarbon-based pesticides from drinking water.
Gold and its alloys have been used for decorative purposes for more than 6,000 years. As with the other applications this use is attributable to the unique combination of properties gold offers: its unique appearance, color and beauty, the ease with which it can be fabricated and its corrosion resistance.
Why Own Gold?
In contrast to other commodities, gold does not perish, tarnish or corrode, nor does gold have quality grades . Gold mined thousands of years ago is no different from gold mined today. Therefore, gold existing in the aboveground gold stock is interchangeable with newly mined gold.
As banking crises occur, the public begins to distrust paper assets and turns to gold for a safe haven. Gold has often been called the "crisis commodity" because it tends to outperform other investments during periods of world tensions. The very same factors that cause other investments to suffer cause the price of gold to rise. A bad economy can sink poorly run banks. Bad banks can sink an entire economy. And, perhaps most importantly to the rest of the world, the integration of the global economy has made it possible for banking and economic failures to destabilize the world economy.
When all else fails, governments rescue themselves with the printing press, making their currency worth less and gold worth more. Gold has always risen the most when confidence in government is at its lowest.
In the coming decade, as the dollar suffers one of the great meltdowns in monetary history, gold will reclaim its place at the center of the global financial system. Gold’s value, relative to most national currencies, will soar. “When East Central Bank buying outstrips West Central Bank selling, and it will in the not-too-distant future, the other remarkably bullish fundamentals for gold will take over and drive the gold price to levels that most people can scarcely imagine.
Despite negative publicity, mining plays an essential role in our everyday lives
Minerals are a vital component in nearly every activity we do. Turning on a light switch, walking on sidewalks, brushing our teeth, the change in our pocket, using cosmetics, computers, fertilizers, and so much more involves using minerals that have been mined. It is estimated that 10 tons of minerals must be mined annually for every persons use.
Talc, a mineral mined in the U.S., is used in baby powder, cosmetics, rubber, ceramics, paint and paper, just to name a few everyday items. Gold has many uses, including jewelry, computers, glass production, and even in the treatment of rheumatoid arthritis. Copper is used in our daily activities. Millions of miles of copper wire is used to transfer electricity to our technology-driven lives. Think about the stone in our sidewalks and roadways. The stone that is used to make concrete and pavement must be mined in quarries. Even fly ash from coal combustion is used in many road materials.
The most common mineral that is mined is coal. Coal is used for electricity generation and for other industries, such as steel manufacturing. In a booming technology age, electricity demands are soaring. About 68 percent of steel production worldwide comes from iron, which is made of iron ore, coke (carbonized coal), and small quantities of limestone. Anthracite coal is used for water filtration purposes in water treatment facilities. Goods and services such as the food in your grocery store rely on mining because nearly every workplace in every industry uses some form of petroleum, metals, and aggregates.
When it comes right down to it, mining provides a critical element in the manufacture of almost everything we eat, wear, ride in, work with, and live in. ~