Silver Basics

Silver Usage

The uses of silver stem from its unique properties comprising anti-bacterial qualities, corrosion resistance, malleability, ductility, reflectivity and conductivity have resulted in ever increasing possibilities for a myriad of other industrial applications, to add to its traditional uses in jewellery and photography

Industrial Uses

Silver is predominantly an industrial metal with over 51% of world demand consumed by industry.  According to the authoritative GFMS “World Silver Survey2007” in 2006 industrial demand for the metal  rose for the fifth consecutive year to 430 million ounces.  Silver’s industrial uses are the result of unique properties including:

  • The Highest Thermal conductivity of all metals
  • The Highest Electrical conductivity of all metals
  • The Highest Reflectivity of all metals

The best known industrial applications are in electronic applications:

  • Silver has widespread applications in electronics, arising from its high conductivity.  In fact silver is defined as having electrical conductivity of 100 against which other metals such as copper (97) and gold (76) are measured.
  • Silver does not ‘spark’ unlike any other metals and is therefore used to make electrical contacts where there are risks from fire or explosion.
  • Silver has the unique ability to join many metals at temperatures far below their melting points, and is replacing tin/lead solder in many applications, having the added benefit of eliminate the use of environmentally unfriendly lead. An EU law comes into effect on 1 July 2006 banning the use of lead based solders with tin/silver/copper solder being the primary replacement. Some 43.5m ounces of silver was used for solder and brazing worldwide in 2006, and the EU law change is likely to significantly increase this.
  • Silver is utilised in batteries where dependability is mandatory and weight is critical, such as those for portable surgical tools, hearing aids, pacemakers and space travel.
  • Silver tape is a critical component of superconductive cabling. This cabling can carry far more electrical current than conventional wire with far less resistance (and thus generating less heart) and in much smaller spaces. With these characteristics it is destined to be increasingly used in power grids of the future, especially in towns and cities where space is at a premium and the existing power infrastructure must carry greater current loads. Vitaly Ginzburg, Alexei Abrikoosov and Anthony Leggett were jointly awarded the 2003 Nobel prize in Physics in December 2003 for their pioneering work in superconductors and superfluids, which utilise silver as a key material.
  • Silver’s attributes are being used to develop new flat screen display technology. These slim flat screens are fast replacing the cumbersome cathode ray tube television screens. A Flat panel displays consist of two parallel flat sheets of glass. On the back of the glass screen facing the viewer is a grid of thousands of lines of silver, each thinner than a human hair, which conduct the electronic signals which in turn activate a gas that hits colour phosphors and more lines of silver on the second sheet of glass. On impact, these colour phosphors react by flashing colour to create the picture seen by the viewer.
  • Silver is also used as a catalyst  in the manufacture of plastics and in the petrochemical industry

Less well known industrial applications include:

  • Silver has a pure sweet acoustic resonance, better than any other metal, and is used to manufacture high quality silver bells and musical instruments.
  • Silver can be used in certain medical treatments as in ionic form, silver kills bacteria by breaking down their cell walls, yet it is inert in the human body. No silver-resistant bacterial strains are known to exist. Silver rich creams are used to treat burns whilst its relatively inert property results in it being commonly used to pin fractured bones, and sew large wounds.
  • Silver has silver medicinal uses in eye drops, nasal spray and burn ointments.
  • Silver is the best heat conductor of all metals, a characteristic resulting in silver’s use in solar panels and automobile rear window heaters.
  • Silver is increasingly replacing the use of chlorine, which is now thought to have long-term toxic effects, in water filtration systems for hospitals, apartments, pools, schools and municipalities.
  • Silver compounds are starting to replace conventional wood preservatives (for decking, outdoor furniture, railroad ties, telephone poles, etc.) which use arsenic compounds, which are toxic to the environment.
  • Similarly paints containing silver compounds may gradually replace those currently used for marine anti-fouling coatings for boats, docks, piers, etc.
  • In recent years major progress has been made towards advancement of new silver-based catalytic converters, culminating in the passage of the 2003 version of the United States House of Representatives energy bill. This allows the US government to study the use of silver in the automotive catalytic process to be explored, researched and tested by a three-year program financed by the government of the United States. The potential increase use of silver could be immense

A unique range of chemical and anti bacterial properties which are finding new applications

Jewellery, Silverware, Mirrors and Coinage

Over 30% of silver is consumed as jewellery, coinage and silverware.  Sterling silver contains 92.5 percent silver and 7.5% copper. 14 Carat gold consists of 53% gold, 25% silver and 22% copper. Silver is commonly alloyed with gold or copper to manufacture jewellery and silverware.

  • Silver has been used as a human adornment since the beginning of time as it can be buffed to a higher polish than any other metal. The same quality is critical to its use in mirrors silverware and reflective coatings on glass, cellophane and metals. In addition to mirrors being used for vanity purposes mirrors are important components in telescopes, microscopes and solar panels.
  • As a precious metal, silver is also used in coins, sometimes alloyed with other metals, in many countries. The US Strategic Defence Stockpile contained approximately 2 billion ounces of silver after World War 2 , the last of which was delivered to the US Mint in 2001. Any future US coins containing silver will need to be acquired in the open market.
  • in consumer, business, medical and other products.

Photography

In 2006, approximately 17% of the world's annual silver supply was consumed in photography; a decline of around 10% on the previous year and the seventh consecutive year of decline in silver’s use in photography. 

  • Digital photography is leading to a reduction in demand in developed countries, but this has been partially offset by strong demand for photographic products from developing countries where recycling tends to be less developed and there is very limited digital technology.
  • All of the silver in colour film processing is kept in the developing solution which can result in 100 percent recycling, although some users do not succeed in this.
  • X-rays account for 30 to 40 percent of the silver used in photography annually, and the number of x-rays taken each year is rapidly growing. Although digital imaging is growing in western countries, increasing use of more traditional X-ray methods in developing countries continues to support silver demand.