Silver Uses: Modern Applications
Silver has been used by mankind for thousands of years and but its main uses have undergone dramatic changes over time. While silver's use as a store of value has diminished over time, newer applications have arose to replace demand for this precious metal.
As technology advanced over the past decades, silver has found additional uses in areas such as electronics and photography and these new applications consume a large proportion of silver mined every year.
Modern applications such as x-ray photography have largely replaced silver's traditional role as money.
A particular group of silver compounds known as silver halides are extensively used in the photography industry to make films for capturing images. Silver halides are chemical compounds of silver with a halogen - typically bromine, chlorine and iodine - and they are the light sensitive ingredient used in photographic film.
When exposed to light, silver halide crystals form metallic silver that turns black when developed. To make photographic film or paper, an emulsion of silver halide crystals in gelatin is coated on to a film base, paper or glass substrate. A single ounce of silver can produce enough silver halides to take 5000 photographs.
Light sensitive silver halides are the main ingredients used in the making of photographic films.
While the photography industry is one of the largest consumers of silver, demand is gradually falling due to increased competition from digital imaging technology.
Silver is a visibly clean, attractive and strong metal ideal for contact with food and mouth. It is one of the most chemically inert of metals and does not react with acids present in fruit, fish and sauces etc. Hence, it became a popular choice for making tableware - cutlery, flatware and holloware - for daily use such as dinner knives, forks and spoons, serving dishes, drinking vessels, tea and coffee services etc.
The attractive and chemically inert silver is the ideal metal of choice for producing fine tableware.
At the height of the silver craze, during the 50-year period from 1870 to 1920, flatware lines sometimes included up to 100 different types of pieces. In addition to the regular dinner knives, dinner forks and spoons, there were butter spreaders, place knives, cheese knivse, fruit knives, salad forks, pastry forks, shrimp or cocktail forks, place forks, bouillon spoons, demitasse spoons, iced tea spoons and gumbo soup spoons.
Silverware is made of sterling silver, an alloy combining 92.5% silver with 7.5% other metal, usually copper. Sterling silver is ideal for making silverware as it possesses strength, malleability and an ability to attain a high degree of polish.
Today, silverware sets remain popular gifts for christenings, weddings and anniversaries and silverware remains one of the top consumers of silver worldwide.
Electrical & Electronics
Next to jewelry/silverware and photography, the third largest consumer of silver is in the electrical/electronics sector where silver solders and pastes are increasingly being used to make electronic circuits, contacts and chips. The rise of the information technology has led to a proliferation of consumer electronic products/gadgets such as digital cameras, personal digital assistants (PDA), cell-phones and mp3 players, resulting in explosive demand for electronic chips. Increased environmental concerns calling for lead-free solders to be used for consumer electronics products are also helping to fuel additional demand for silver in this area.
Silver is increasingly being used in the electronics industry as the information boom continues.
While the good news is that the electronics industry is rapidly expanding with more chips produced every year, increased manufacturing efficiency led to introduction of thrifting processes designed to reduce the amount of silver used in each chip, contact and circuit. Furthermore, the size of circuits within each chip is also shrinking, further reducing the amount of silver required per chip.
Besides allowing electricity to flow, silver is also used to generate electrical power. Silver is used to make silver-oxide batteries, otherwise also known as silver-zinc battery. Silver-oxide batteries have a high energy-to-weight ratio, making them ideal for applications that require long battery life. However, due to the high cost of silver, such batteries are often only used in expensive or mission critical products where concerns over costs is overshadowed by the need for either space, reduced weight or longevity. Examples where silver-oxide batteries are used are in digital wrist-watches where space is limited and in powering military hardware where the cost of the battery is insignificant next to winning battles and keeping the soldiers alive on the battlefield.
Silver is one of humanity's first defense against bacteria. For centuries, the antiseptic properties of silver has been used by civilizations throughout the world. The ancient Roman legions wrapped thin silver foil around wounds received in the battlefield, preventing the wounds from becoming infected and thus enabling them to close rapidly. Kings and queens ate and drank from silver plates and silver goblets, not only to show off their wealth and power, but also as a protection against diseases. Back in the early 1900s, silver dollars were placed inside milk bottles to keep milk fresh.
Silver's anti-bacteria properties has been known since thousands of years ago.
The rise of antibiotics in the second half of the 20th century took the shine off silver's time-tested prowess as a versatile antiseptic. However, as time goes by, more and more bacteria are developing resistance to antibiotic drugs. Nowadays, researchers have returned to silver for another look, this time armed with nanotechnology.
Using nanotechnology, scientists are able to coat medical instruments and devices with a microscopic layer of silver particles. Bacteria that come into contact with the silver particles have very little chance of survival. The silver ions released by the silver particles attack the bacteria by destroying the enzymes that transport cell nutrients, weakening the cell membrane and disrupting cell division and proliferation processes.